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Red, etc., which have a steep declivity, but flow in broad, shallow valleys, are examples.

This matter is fully discussed by Powell in the report above cited (1876), and by Gilbert in his report on the Henry Mountains (1880).

RUSSELL HINMAN. Cincinnati, O., Aug. 27.

[Our esteemed correspondent misapprehends the scope and specific limitations of this “new law in the hydraulics of rivers," as he also does those of the law announced by Major Powell in his report on the Uinta Mountains, in 1876. In neither case is the law stated as a general one. Major Powell has never said, and does not now say, that in all rivers, and under all circumstances, rasion of every kind is increased by increase of load," although it may be true. But that is what our correspondent seems to suppose Major Powell's law of 1876 meant. Stated in its simplest form, the law of 1876 is as follows: “In a region of degradation, vertical corrasion is increased by increase of load, in a diminishing ratio." He never dreamed at that time that this law could be generalized, or even that any similar law would explain lateral corrasion by a river flowing through a flood-plain. The new law which he now proposes as the result of subsequent study is, In a region of sedimentation (and it must be noted that the flood-plain of the Mississippi is a delta region, and therefore a region of sedimentation) an increase of load increases lateral corrasion in a geometric ratio." We did not emphasize this distinction in the brief editorial reference which we made to Major Powell's paper, assuming that any reader who had given especial attention to the study of the hydraulics of rivers would make it for himself, certainly if he read Major Powell's paper printed in the same number of Science, and beginning on the same page with the editorial paragraph referring to it; for all others the law was stated in the least confusing, although perhaps not in the most comprehensive language. — Ed.]

the summer, to the delight of myself and friends. Of course. I awaited the opening of spring with anxiety, to know if our birdie would return. Almost the first song of spring, sure enough, was one morning in April: - Hear this birdie! Hear this birdie!" But, better yet, it was apparent that the babes of this family were singing, not the old robin's see-saw, but the new song. And now about my place are three or four of our birdies. What was notable was not only the remarkable evolution of musical power, but a love for music; for our birdie, unlike the robins in general, sang all day, like the catbirds. I could hear one or more at almost any hour. This drew my attention to the cause of the unexpected variation. John Burroughs suggested that it might be the song taught to one that had been caged and afterwards escaped ; but I am more inclined to think that it is a natural variation or evolution, and that the robin has great and undeveloped power. It is a phlegmatic bird, that takes the world easy, and is not likely to exert itself in new directions. The catbird is fond of notice, likes to be whistled to, and enjoys answering back. He is likely to develop all sorts of new vocal accomplishments. But the robin is really lazy, and does as little hard work as possible. His nest is a clumsy affair, a mere daub of mud and sticks. Why has he begun this new song? Is it from being so constantly with catbirds, grossbeaks, orioles, etc. ? for my nine acres are the paradise of birds. They are covered with fruits, hedges, trees. I do not know, but believe, some such cause to be at the bottom of the affair, and that we may look for other developments quite as remarkable. Within the month of June, while driving about five miles from my home, I saw a robin sitting on a wayside fence, and singing a set of notes most charmingly unlike any thing I had ever heard; neither was it at all like our birdie. It was as complex as a catbird often sings, but not apparently imitative. This has led me to a very decided conviction that an evolution in robin-music is now going on, and that some very delightful results may be looked for. I shall be glad to get notes from observers in different parts of the country. Of this I am certain, that our common thrush has a vast vocal power undeveloped. Evolution with birds must move, as it has moved, in the line of music, plumage, and fight, and nest-building. Nothing in these directions need surprise us.

I subjoin a note taken from a paper published near New York City, over two hundred miles from here: “ Thomas O'Donnell of Rondout has a robin which whistles like a mocking-bird. This is probably due to the fact that it was raised in company with a mocker. The robin whistles · Johnny, get your Gun,' and `Don't leave your Mother, Tom !' Its powers of mimicry are wonderful. In the early morning, when things are quiet, the whistle of the bird has been heard a quarter of a mile. One day recently a man went into a saloon over the door of which the robin hung. The bird gave a sharp, quick whistle, which a man across the way, seeing his friend enter the saloon, considered a call to get a free drink. The man who first entered the saloon denied having whistled, but he nevertheless stood treat." I am confirmed by such reports in the belief that we shall see a remarkable evolution of robin-music. Our homestead pet and universal favorite will then be all the more dear.

E. P. POWELL. Clinton, N.Y., Aug. 28.

A Notabie Evolution.

The remarkable power of the catbird as a singer is known to all those who give it a safe and welcome retreat. Yet I find even such writers as Baird describing it after this manner : “ An American bird of the thrush family, whose cry resembles the mewing of a cat.” In reality it is the mocking-bird of the North, possessed of ability to sing whatever notes he hears. I have them so perfectly at home in my grounds, that their delicious music is heard at all hours of the day, and often in the middle of the night. It is very curious to hear one of them warble in a low key to himself what some other bird is singing loudly. A few days since I heard one mimic a red squirrel, and he did it to perfection. If he had not enjoyed the fun so well that he could not keep from hopping about, I should not have known which was squirrel.

I did not, however, intend, except incidentally, to write about the catbird, Mimus Carolinensis. It, however, makes it easier for us to conceive the possibility of an evolution of superior vocalization in his relatives, when we consider his masterly ability. What I wish to record is a remarkable development in the case of his cousin the common robin, or migratory thrush. Every one knows what a clumsy singer he is, having a rough, see-saw note, that he repeats with little variation. For some reason the other birds give him precedence in the morning song with which daylight is greeted about half-past three in June. The first note comes always from the east, – a faint, far-away cry; then another cry leaps out of a tree nearer you, and then another and another. So the wave of robin-melody moves westward, over the house and over the land, preceding the rising sun, probably from the Atlantic to the Pacific. This song is peculiarly adapted to constitute a matin cry, being clear, strong, and cordial. But it is not musical. In June of 1887, crossing one of my lawns, I heard a cry so peculiarly like articulation that I was startled : “ Hear this birdie! Hear this birdie ! Hear this pretty birdie !" the last notes being exquisitely rendered, with a wave and upward bend. I had never heard such a song before, and imagined a new species of bird must have arrived; but after careful examination, I found the singer to be a veritable robinedbreast, and not a new-comer at all. The song was repeated all

one.

Queries. 36. DOUBLE Fruit. -- Last May a gentleman brought into my office a peach-tree branch quite thickly covered with small green peaches, most of which were double ; that is, consisted of two (in several cases three) peaches, more or less completely fused into

Some of the members of these doublets were hardly distinguishable as such, except by the fact that they had two stones ; while others were scarcely united, and a few were entirely distinct from each other, but had only a single stem. Later I learned of such peaches being common in two other widely separated localities in this State this year, but no one had ever seen them in any previous year. I have also a collection of ripe cherries doubled in a similar way, and gathered this year from a tree in this city. Is this a common phenomenon ? What is the appearance of the flower which gives rise to this double fruit? J. L. H.

Louisville, Ky., Aug. 7.

SCIENCE

FRIDAY, SEPTEMBER 14, 1888.

writer how he knew that there was such a thing as speech, and that he would ever be able to exercise that faculty.

so."

THE YELLOW-FEVER IN JACKSONVILLE, although of a mild type and attended by an unusually small mortality, has become epidemic there. The United States Marine Hospital Service, under the authority given it by the new quarantine law and previous acts of Congress, has undertaken to prevent the spread of the disease from the infected points in Florida to other cities of the country. It is certain that every person, and every article of clothing, baggage, or of any other description, that comes out of Jacksonville, is in danger of conveying the infection to points which it otherwise might not reach. This is Surgeon-General Hamilton's justification for his order forbidding any person, baggage, or mail-matter to pass the quarantine station at Waycross, Ga., which is so situated as to intercept all railway-passengers from Florida, if from an infected district, without a quarantine of ten days for persons and a thorough disinfection of all clothing, baggage, and mail-matter. This, of course, causes very great inconvenience to those people of Jacksonville who desire to leave the city for healthful points in the North ; but Dr. Hamilton has provided a refugee-camp, where any person may spend the period of quarantine free of expense, and in as much comfort as it is possible to give under the circumstances. These are the precautions that have been taken to protect the sixty millions of the people of the United States from sickness and death. It is unfortunate for the comparative few who have to suffer by detention in Jacksonville and other infected points in Florida ; but the fact that more than a month has passed since the disease first appeared in Jacksonville, Tampa, and other points in Florida, and that not an authentic case has yet been reported as having occurred this side of the government quarantine station, is more than an ample justification for every thing Surgeon-General Hamilton has done. It may be that the yellow-fever will yet be carried to points outside of Florida. The most careful precautions are necessarily imperfect : they may sometimes be evaded, in spite of the most vigilant watchfulness. But every day that the contagious disease is confined within its present limits shortens the time that its ravages can continue elsewhere before the autumn frosts cut it short in its destructive career, and saves precious lives that else might have been sacrificed. If Surgeon-General Hamilton should succeed in preventing the spread of the yellow-fever beyond Florida, he will have rendered a service to the country that can never be measured in money. He deserves the most cordial support, which he is receiving, not only from the government, but also from the public press and enlightened public sentiment throughout the country.

THE ATTENTION OF OUR READERS has already been called to the passage by the Legislature of New York of an act substituting death by electricity for that by hanging as a punishment for crime. It will be remembered that Dr. William A. Hammond regarded the change as an unwise one, and presented a paper to the Society of Medical Jurisprudence on the Superiority of Hanging as a Method of Execution. The society concurred in the views therein expressed, and protested against the passage of the law. In the Asclepiad, Dr. B. W. Richardson agrees in the main with Dr. Hammond. He believes that death by hanging is painless, and that the “process of hanging looks brutal without actually being

He is especially severe on those who advocate the change. He says, “In disgust at the foolish barbarism of the time which keeps up the crime of capital murder, the humanitarian fraternity, afraid to support the sound and logical policy of abolition of the extreme offence, tries to dally with reason and conscience by the attempt to divest execution of all pain and all terrors. Euthanasia for the worst of criminals, by the side of so-called natural but often most cruel death for the rest of mankind, is practically the proposition, a proposition which carries with it its own condemnation." In regard to the practicability of the new law, he expresses a great deal of doubt. In some experiments on the application of the electric discharge for the painless extinction of the lives of animals to be used as food, this mode of death was found to be any thing but certain. Sheep stricken apparently into instant and irrevocable death by electricity, after a few minutes showed signs of life, and were despatched in the ordinary way by the knife; and a large dog perfectly unconscious, and to all appearance dead, from the stroke of a powerful battery, was submitted to a surgical operation during unconsciousness, and afterwards made a sound and easy recovery. In most cases the electric shock will kill at one discharge, but exceptionally it will simply stun, and may induce the semblance of death instead of the real event. Dr. Richardson thinks that it will be real humanity, therefore, for the authorities of New York to supplement death by electricity by a post-mortem examination of the victims, so that the execution may not be crowned by burying the victims alive,

IN A RECENT NUMBER of The Medical News appeared a note from a correspondent whose professional eminence is an unqualified indorsement of the accuracy of his observation, in which he writes, “ I have recently seen in the medical journals that Dugald Stewart was once asked what was the earliest thing he could remember. He said it was being left alone by his nurse in the cradle, and resolving to tell of her as soon as he could speak. This may have been copied as a joke; but it brings to my mind the following statement that I have made from time to time for many years, which has always been received with derision, but which is a perfectly distinct remembrance in my mind : I remember being jolted over the crossings in a baby-wagon by a nurse, and resolving to tell of her as soon as I could speak." In reading the above, it occurred to us that it would not be amiss to ask the

ON THE ALLEGED MONGOLIAN AFFINITIES OF THE

AMERICAN RACE." WERE the question I am about to discuss one of merely theoretical bearings, I should not approach it; but the widespread belief that the American tribes are genealogically connected with the Mongolians is constantly directing and coloring the studies of many Americanists, very much as did at one time the belief that the red men are the present representatives of the ten lost tribes of Israel. It is practically worth while, therefore, to examine the grounds on which the American race is classed by these anthropologists as a branch of the Mongolian, and to inquire whether the ancient culture of America betrayed any positive signs of Mongolian influence.

You will permit me to avoid the discussion as to what constitutes races in anthropology. To me they are zoological sub-species, marked by fixed and correlated characteristics, impressed so firmly that they have suffered no appreciable alteration within the historic period either through time or environment. In this sense, Blumen

1 Paper read by Daniel G. Brinton, M.D., before the American Association for the Advancement of Science, at its meeting in Cleveland, O., Aug. 15-22, 1888.

bach, in the last century, recognized five races, corresponding to antiquary Mendoza has marshalled far more coincidences of like the five great land-areas of the globe and to their characteristic character and equal worth to show hat the Nahuatl is an Aryan faunal and floral centres. This division was an eminently scientific dialect descended from the Sanscrit. In fine, any, even the remotone, and still remains the most in accord with anatomical and lin

est, linguistic connection between American and Mongolian languistic research. About twenty years after the appearance of Blu guages has yet to be shown; and any linguist who considers the menbach's work, however, the eminent naturalist Cuvier published radically diverse genius of the two groups of tongues will not exhis great work on The Animal Kingdom,' in which he rejected pect to find such relationship. Blumenbach's classification, and proposed one dividing the human I shall not detain you long with arguments touching supposed species into three races, — the white or Caucasian, the black or Mongolian elements of culture in ancient America. Any one at all Ethiopian, and the yellow or Mongolian. In the latter he included intimately conversant with the progress of American archæology the Malays and the American Indians.

in the last twenty years must see how rapidly has grown the conThis triple division has been very popular in France, and to some viction that American culture was home-bred, to the manner born; extent in other countries. It is not, and it was not in its inception, that it was wholly indigenous and had borrowed nothing — nothing a scientific deduction from observed facts, but was a sort of a priori from either Europe, Asia, or Africa. The peculiarities of native hypothesis based on the physiological theories of Bichat, and at a American culture are typical, and extend throughout the continent. later day derived support from the philosophic dreams of Auguste Mr. Lewis Morgan was perfectly right in the general outline of his Comte. Bichat, for instance, had recognized three fundamental theory to this effect, though, like all persons enamored of a theory physiological systems in man, the vegetative or visceral, the osso he carried it too far. muscular, and the cerebro-spinal. The anthropologists, in turn, This typical, racial American culture is as far as possible, in considered it a most happy thought to divide the human species spirit and form, from the Mongolian. Compare the rich theology into three races, each of which should show the predominance of of Mexico or Peru with the barren myths of China. The theory of one or other of these systems. Thus the black race was to show governments, the method of house-construction, the position of the predominance of the vegetative system; the yellow race, the woman, the art of war, are all equally diverse, equally un-Monosso-muscular system ; the white race, the nervous system. As golian. It is useless to bring up single art-products or devices, Bichat had not discovered any more physiological systems, so there such as the calendar, and lay stress on certain similarities. The could be no more human races on the earth; and thus the sacred doctrine of the parallelism of human development explains far more triplets of the Comtian philosophy could be vindicated.

satisfactorily all these coincidences. The sooner that Americanists How little value attaches to any such generalizations you will generally, and especially those in Europe, recognize the absolute readily perceive, and you will be prepared, with me, to dismiss autochthony of native American culture, the more valuable will them all, and to turn to the facts of the case, inquiring whether their studies become. there are any traits of the red race which justify their being called It is no longer in season to quote the opinions of Alexander von • Mongolian' or Mongoloid.'

Humboldt and his contemporaries on this subject, as I see in some Such affinities have been asserted to exist in language, in culture, recent works. The science of archæology has virtually come into and in physical peculiarities, and I shall take these up seriatim for being since they wrote, and we now know that the development of examination.

human culture is governed by laws with which they were unacFirst, as to language.

quainted. Civilization sprang up in certain centres in both conThe great Mongolian stock is divided into the southern branch, tinents, widely remote from each other; but, as the conditions of speaking monosyllabic, isolating languages, and the northern its origin were everywhere the same, its early products were much branch, whose dialects are polysyllabic and agglutinating. The alike. latter are sometimes called Turanian or Ural-Altaic; and as they It is evident from what I have said, that the asserted Mongolian are geographically contiguous to the Eskimo, and almost to the or Mongoloid connection of the American race finds no support Athabascan, we might reasonably expect the linguistic kinship, if either from linguistics or the history of culture. If anywhere, it any exists, to be shown in this branch of Mongol speech. Is such must be in physical resemblances. In fact, it has been mainly from the case ? Not in the least. To prove it, I think it enough to these that the arguments have been drawn. Let us examine quote the positive statement of the best European authority on the them. Ural-Altaic languages, Dr. Heinrich Winkler. He emphatically Cuvier, who, as I have said, is responsible for the confusion of says, that, in the present state of linguistic science, not only is there the American with the Mongolian race, based his racial scheme on no connection apparent between any Ural-Altaic and any American the color of the skin, and included the American within the limits language, but that such connection is shown to be highly improb- of the yellow race. Cuvier had seen very few pure Mongolians, able. The evidence is all the other way (Uralaltaische Völker and perhaps no pure-blooded Americans; otherwise he would not und Sprachen, p. 167).

have maintained that the hue of the latter is yellow. Certainly it I need not, therefore, delay over this part of my subject, but will is not. You may call it reddish, or coppery, or cinnamon, or burnt proceed to inquire whether there are any American affinities to the sugar, but you cannot call it yellow. Some individuals or small monosyllabic, isolating languages of Asia.

tribes may approach the peculiar dusky olive of the Chinaman, but There is one prominent example, which has often been put for so do some of the European peoples of Aryan descent; and there ward, of a supposed monosyllabic American language; and its are not wanting anthropologists who maintain that the Aryans are relationship to the Chinese has frequently been asserted,

a rela

also Mongoloid. The one position is just as defensible as the tionship, it has been said, extending both to its vocabulary and its other on the ground of color. grammar. This is the Otomi, spoken in and near the valley of Several of the most prominent classifications of mankind are Mexico. It requires, however, but a brief analysis of the Otomi to based upon the character of the hair ; the three great divisions see that it is not a monosyllabic language in the linguistic sense, being, as you know, into the straight, the curly, and the woolly and that in its sentence-building it is incorporative and polysyn haired varieties. These external features of the hair depend upon thetic, like the great majority of American tongues, and totally the form of the individual hairs as seen in cross-section. The unlike the Chinese. I may refer to my own published study of nearer this approaches a circle, the straighter is the hair. It is the Otomi, and to that of the Count de Charencey, as proving what true that both Mongolians and Americans belong to the straight

haired varieties; but of the two, the American has the straightest Some have thought that the Maya of Yucatan has in its vocabu hair, that whose cross-section comes nearest to a perfect circle. So lary a certain number of Chinese elements; but all these can that by all the rules of terminology and logic, if we are to call readily be explained on the doctrine of coincidences. The Mexican either branch a variation from the other, we should say that the

Mongol is a variety of the American race, and call it ‘Americanoid' 1 See Foley, Des Trois Grandes Races Humaines, Paris, 1881.

instead of vice versa. ? I do not think that the verbal coincidences pointed out by Petitot in his Monographie des Déné Dindje, and by Platzmann in his Amerikanisch-Asiatische Ety

The color of the hair of the two races is, moreover, distinctly mologien, merit serious consideration.

different. Although superficially both seem black, yet, observed

I say.

carefully by reflected light, it is seen that the ground-tone of the totally un-Mongolian in cranial shape, in nasal index, and in linMongolian is bluish, while that of the American is reddish. guistic character. They do possess in some instances a general

Of positive cranial characteristics of the red race, I call attention physiognomical similarity, and this is all; and this is not worth to the interparietal bone (or os Ince), which is found in its extreme much as against the dissimilarities mentioned. The same is true development in the American, in its greatest rarity among the Mon of the differences and similarities of some tribes of the north-west golians; also to the form of the glabella, found most prominent in coast. In estimating the value of any resemblances observed in American crania, least prominent in Altaic or northern Mongoloid this part of our continent, we should remember that we have sufficrania; and the peculiar American characteristics of the occipital cient evidence to believe that for many generations some slight bone, flattened externally, and internally presenting in nearly forty intercourse has been going on between the adjacent mainlands and per cent of cases the ‘Aymarian depression,' as it has been termed, islands of the two continents in the regions of their nearest proxinstead of the internal occipital protuberance (HERVELACQUE et imity. The same train of events led to a blending of the negro HERVÉ, Anthropologie, pp. 231, 234, 236).

and the white races along the shores of the Red Sea; but any one The shape of the skull has been made another ground of race who recognizes the distinction of races at all — and I am aware distinction; and, although we have learned of late years that its that certain eccentric anthropologists do not — will not, on that value was greatly over-estimated by the earlier craniologists, we account, claim that the white race is negroid. With just as little have also learned that in the average, and throughout large num reason, it seems to me, has it been argued that the native Ameribers of peoples, it is a most persistent characteristic, and one cans as a race are Mongoloid. potently indicative of descent or relationship. Now, of all the peoples of the world, the Mongols, especially the Turanian branch, are the most brachycephalic; they have the roundest heads; and

ON THE CAUSES OF VARIATION IN ORGANIC it is in a high degree noteworthy that precisely the American

FORMS. nation dwelling nearest to these, having undoubted contact with

The fundamental principle of organic evolution is natural selecthem for unnumbered generations, are long-headed, or dolicho tion, which is based on individual variation and the struggle for cephalic, in a marked degree. I mean the Eskimo, and I cannot

existence, the effect of which is the preservation of the most combut be surprised that such an eminent anthropologist as Virchow

petent. It is extremely difficult to get at the immediate cause or (in Verhandlungen der Berliner Anthrop. Gesellschaft, 1881-82), causes of this individual variation, and for this reason Darwin conin spite of this anatomical fact, and in defiance of the linguistic evi sidered it promiscuous and aimless, though he wisely avoided calldence, should have repeated the assertion that the Eskimo are of ing it lawless. There is no more fascinating or profitable field of Mongolian descent.

investigation than that leading to the proximate cause or causes of Throughout the American continent generally, the natives were

variation. We are not content to rest the case where Darwin did not markedly brachycephalic. This was abundantly illustrated

by recognizing variation as an inherent principle in organic forms, more than twenty years ago by the late Prof. James Aitkins Meigs,

or to beg the question by saying that it is as much a necessity of in his Observations on the Cranial Forms of the American Abo life as natural selection itself. Let us, therefore, discuss these rigines. They certainly, in this respect, show no greater Mongoloid causes in the light of recent experience and experiment. affinities than do their white successors on the soil of the United

We soon find that they admit of a certain amount of classificaStates.

tion, the minor divisions of which, as in all systems of classification, If color, hair, and crania are thus shown to present such feeble more or less fully interlock or blend. They fall, however, into two similarities, what is it that has given rise to a notion of the Mongoloid chief categories: viz., (1) external conditions or environment, which origin of the American Indian ? Is it the so-called Mongolian eye, are, at bottom, physical ; and (2) internal tendencies or promptings, the oblique eye, with a seeming droop at its inner canthus? Yes,

which are, at bottom, psychical. a good deal has been made of this by certain writers, especially by By external conditions or environment, we include all influences travellers who are not anatomists. The distinguished ethnologist

on organisms which act from without; and in carefully considering Topinard says the Chinese are very often found without it, and I

them we shall find it difficult to draw the line between those which can confirm this opinion by those I have seen in this country. It is, are really external and independent of any motive or inherent tenindeed, a slight deformity, affecting the skin of the eyebrow only. dency in the organism, and those which are not. Hence the genand is not at all requent in the white race. Surgeons know it

eral term 'external conditions' is resolvable into various minor under the name epicanthus, and, as with us it is considered a dis

factors. figurement, it is usually removed in infancy by a slight operation.

No one can well study organic life, especially in its lower maniIn a few American tribes it is rather prevalent, but in most of the festations, without being impressed with the great power of the pure Indians I have seen, no trace of it was visible. It certainly environment. Joseph LeConte speaks of the organic kingdom lying, does not rank as a racial characteristic.

as it were, “ passive and plastic in the moulding hands of the enThe nasal index has been recommended by some anatomist as vironment.” In Semper's · Animal Life' we have the best systeone of the most persistent and trustworthy of racial indications.

matized effort to bring together the direct causes of variation; and The Mongolian origin of the red race derives faint support from

no one who has read through its pages can doubt the direct modithis quarter. From the measurements given in the last edition of

fying influences of nutrition, light, temperature, water at rest and Topinard's work (Elements d'Anthropologie, p. 1003), the Mongo

in motion, atmosphere still in motion, etc., or question his conlian index is 80, while that of the Eskimo and tribes of the United

clusion that no power which is able to act only as a selective and States and Canada, as far as observed, is 70, that of the average

not as a transforming influence can ever be exclusively put forth as Parisian of to-day being 69 (omitting fractions). According to this

a causa efficiens of the phenomena. test, the American is much closer to the white than to the yellow

It is among the vital or organic conditions of variation that nat

ural selection has fullest sway; and, as they have been so ably Most of the writers (for instance, Avé-Lallemant, St. Hilaire, expounded by Darwin and others, I will at once pass to a considPeschel, and Virchow) who have argued for the Mongoloid charac eration of the second class of causes, to which the study of the ter of the Americans have quoted some one tribe who, it is asserted, interaction of organisms leads, — the internal conditions. shows marked Chinese traits. This has especially been said of the First of these we will consider the physiological causes. Genesis natives of three localities, - the Eskimo, the tribes of the North

itself is the first and most fundamental of all causes of variation. Pacific coast, and the Botocudo of Brazil. So far as the last-men

The philosophy of sex may, indeed, be sought in this differentiationed are concerned, the Botocudo, any such similarity has been tion, as the accumulated qualities in separate entities, when suddenly categorically denied by the latest and most scientific traveller who conjoined or commingled, inevitably lead to aggregation and heterohas visited them, Dr. Paul Ehrenreich. It is enough if I refer you geneity; in other words, to plasticity or capacity to vary. Genesis, to his paper in the Zeitschrift für Ethnologie for 1887, where he dismisses, I should say once for all, the notion of any such resem

1 Abstract of an address before the Section of Biology of the American Association

for the Advancement of Science, at Cleveland, O., Aug. 15-22, 1888, by C. V. Riley, blance existing. I have already pointed out that the Eskimo are vice-president of the section.

race.

as a fundamental factor in evolution, may be more intelligently we give importance to the ideas of Lamarck, and, conversely, less considered under some of its subordinate phases, as heredity, physi- importance to the ideas of Darwin. ological selection, sexual selection, primogenital selection, sexual There are certain important laws which have influenced modifidifferentiation including philoprogeneity, hybridity, etc.

cation, but in no sense can be looked upon as causes of variation. Heredity, as expounded by the ablest biologists and as exempli- They are laws or principles of evolution by which we may account fied in life, is a puissant factor in evolution, and, though essentially for the formation of types, acting, just as natural selection does, in conservative, must, through the marvellous power of atavism, tend differentiating rather than in originating the variation. Acceleration to increase individual variability.

and retardation belong to this class. This law is an attempt to give Physiological selection, as suggested by Mr. Catchpool and as expression and form to a set of facts to which paleontology unexpounded by Romanes, is undoubtedly an important factor in doubtedly points, and which ontogeny substantiates; viz., that cerevolution. Romanes believes that wherever there has been modi tain types may attain perfection in time, and then retrogress and fication of the reproductive organs introducing incompatibility be finally become extinct, and that existing types which are dying out tween two individuals, even where there has been no other change or degenerating exhibit ontogenically the culmination of force and or variation, we have a valid cause of differentiation which in its complexity, followed by decadence, corresponding to the phyloconsequences must be important. Compatibility or fertility be genic history of the type. This law may, perhaps, be substantially tween individuals is of the very essence of selection. Natural stated in this wise : that certain groups acquire some characters selection implies that this sexual divergence is subsequent to or rapidly, while corresponding groups acquire the same characters coincident with divergences in other directions ; physiological selec more slowly, or never acquire them at all; and this brings us to tion, that it antecedes them. This theory implies variation in the another important factor of evolution which serves to give force reproductive organs, or departure from the parental type, in at to the law. It is the acceleration by primogeniture which has been least two individuals of opposite sex simultaneously; and with this elaborated by Hubrecht. He shows, that, in organisms in which admission, for which we are justified in facts, physiological selec the reproductive period covers many years, accelerated develoption will preserve many peculiarities which need have no necessary ment by primogeniture (i.e., as between the first-born and the connection with the exigencies of life.

last-born of any pair and of their posterity) will in time produce Sexual selection may be said to act in two ways, — by conflict of differentiation. The series of the first-born will in the course of the males for possession of the female, or by attractiveness; the time involve many generations at short distances from each other former being most conspicuous among mammals, the latter among whereas the series of the last-born will, on the contrary, consist of birds, and both coming conspicuously into play among insects. It a much smaller number of terms, each separated from its predeis rather difficult to define the limit of sexual selection as a factor cessor by a more considerable distance. Any tendency to variain evolution ; but I would not confound it with another factor, not tion from external or internal influences must needs find more hitherto generally recognized, but which I think must be all-pow numerous occasions to act in the series of the first-born, not only erful, namely, sexual differentiation.

because these have a more composite ancestry, but because they It seems evident that the mere differentiation of sex in itself has necessarily become the most numerous. been an important element in variation. This principle elaborated We are thus led to what have been called 'saltations' in evoluby Brooks as a modification of the theory of pangenesis is a good tion. Although the history of paleontology has continually added one, and in the main the male may be said to be the more complex to our knowledge of past forms, and helped to fill up many gaps in and to represent the progressive, and the female the more simple the evolutional series, and although during the last quarter of a cenand to represent the conservative, element in nature. When the tury it has particularly vindicated Darwin's prophecy that many conditions of life are favorable, the female preponderates, and ex links would yet be found, the substantial truth remains, that gaps ercises a conservative influence. When the conditions are unfavor still occur, and that progress, so far as present knowledge indicates, able, the males preponderate, and, with their greater tendency to has been made by occasional saltations. There have been, it would vary, induce greater plasticity in the species, and hence greater seem, periods of rapid movement, and of comparative repose, or power of adaptation. Sexual differentiation may, I think, be used re-adjustment of equilibrium. Cope concludes that “genera and to include many other variations and differentiations not otherwise higher categories have appeared in geologic history by more or satisfactorily accounted for, and to express the law of the interac less abrupt transitions or expression-points, rather than by uniform tion of the sexes upon one another, inducing great differentiation gradual successions.” entirely apart from the struggle of the males for the possession of The forces of nature are constant, but the phenomena induced the females, or the struggle for existence.

are often paroxysmal. The progressive forces accumulate, while the Last of all I mention hybridity, which has been fully discussed conservative forces resist until at last resistance gives way with by many, and by no one more ably than by Darwin himself. comparative suddenness. There is every reason to believe that the

Among the psychical conditions, the use and disuse of an organ life-movement, in its ascending complexity, has shared this comand its effect upon the offspring of the individual is of prime im mon law. How far the rhythmic tendency in the development of portance. That functionally produced modifications are inherited animal life may be explained by the rapid change of climate, by was the great assumption upon which Lamarck founded his theory migration and the loss of record, or upon the general law that of evolution. Many able naturalists have insisted on it, and in my while there has been progress of the whole there has not necesjudgment there should no longer be any doubt whatever of the sarily been progress of every part, it would take us too far to disfact. The influence of emotion on the individual is closely con cuss in this connection. I think we are safe in saying, however, nected with this category, as strong mental effort may be made to that the facts justify belief that in the evolution of animal life, as in affect special parts of the body.

the evolution of every thing else, progress has often been made by An interesting problem is the influence of the emotion of a waves. mother on her offspring. It is still doubtful whether such influence Having thus considered some of the proximate causes of variareally exists; but, this theory once established, its bearing on evolu tion and some of the more general laws of evolution, we are natution as a prime cause of variation must at once be manifest; for it rally led, in conclusion, to consideration of original or infinite cause. gives not only tangibility to the Lamarckian idea of desire influen Far be it from me to try your patience with any prolonged specucing modification, but also a conception of how infinite mind in lation upon the more profound problems of life and of futurity, nature may act through the finite in directing such modification. which have been dealt with by able men of all times, and with such In my judgment, this factor acts only when, from whatever cause, conflicting and varying results. I shall content myself, in closing, and particularly under the spur of necessity, the emotions are ex with a few words upon those themes which, as biologists, we canceptionally intensified, or the desire strongly centred in some par not ignore, and to which the subjects we have been considering ticular object.

inevitably lead. These psychical factors which we have been considering are Mind as exhibited in organic evolution, however simple or comsubstantially Lamarckian ; and in proportion as we consider them, plex may be its manifestations, is in essence one and the same and get to understand the other direct causes of variation, must force. There is an undoubted gradation from simple sensitiveness

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