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food, carrying the luxury so far as to have them brought alive upon their table, to enjoy the beautiful sight of the changing of their colors in the struggles of death ; and yet every page of his work shows that most of his information respecting the habits of fishes was borrowed from his intercourse with fishermen. The works of Aristotle furnish frequent evidence that his own information upon this class of animals, as far as their habits were concerned, had a similar foundation. But he, as all great naturalists of all times, sifted the reports, sought for more information where it seemed needed, and related only what he knew could be depended upon, however marvellous some of his statements may seem at first sight. There are many facts of this kind related in the works of Aristotle, which have excited considerable doubt, and even led to suspicions respecting the general trustworthiness of his assertions. There are a few passages in his works which have even been questioned more directly. Such is his mention of the habits of the Glanis, in the following passages :
". The fresh-water fishes spawn in the still waters of rivers and lakes among the reeds, as the Phoxinos and the Perke. The Glanis and the Perke give out their spawn in a continuous string, like the frogs; and indeed the spawn is so wound up that the fishermen reel it off, at least that of the Perke, from the reeds in lakes.
"• The larger Glanis spawns in deep waters, some at the depth of a fathom; the smaller in shallower places, especially among the roots of willows or some other tree, and also among the reeds, or the mosses. They copulate, sometimes a very large with a very small one, and bringing the parts together which some call the navel, and through which they discharge the seed, the females the eggs, and the males the sperma. All the eggs that are mingled with the sperma become generally on the first day white and larger, and a little later the eyes of the fishes become visible. These at first, in all fishes, as also in all animals, are early conspicuous on account of their size. And those of the eggs that the sperm does not touch, as in the case of the sea-fishes, are useless and sterile. But in these fertile eggs, as the fishes grow larger, a kind of husk separates. And this is the envelope that encloses the egg and the young fish. When the sperm has mingled with the egg, the spawn becomes more viscous among the roots, or wherever it may have been deposited. And where the greatest quantity is deposited, the male guards the eggs, and the female, having spawned, departs. The growth of the Glanis
from the egg is very slow, wherefore the male keeps watch forty or fifty days, that the young may not be devoured by the fishes that happen to be in their neighborhood.'*
“Of the river fishes, the male Glanis takes great care of its young. For the female, having brought forth, departs ; but the male, where the greatest deposit of eggs has been formed, remains by them watching, rendering no other service except keeping off other fishes from destroying the young. He does this for forty or fifty days, until the young are sufficiently grown to escape from the other fishes. And he is known to the fishermen wherever he may chance to be watching his eggs ; for he keeps off the fishes by rushing movements, and by making a noise and moaning. And he remains by the eggs with so much of natural affection, that the fishermen, when the eggs adhere to deep roots, bring them up to the shallowest place they can; but he does not even then leave his offspring, but if he chance to be a young fish, he is easily taken by the hook, because he snaps at all the fishes that approach him ; but if he is already accustomed to this, and has swallowed hooks before, he does not even then desert his young, but breaks the hook by a very strong bite.' +
“Cuvier, alluding to these passages in the great Histoire Naturelle des Poissons, which he published in connection with Valenciennes, makes the following remarks respecting the fish called Glanis by Aristotle, and its habits :
“ . It cannot be doubted that our Silouros is the rđávis of Aristotle. Besides that it is common in Macedonia, and still bears in Turkey the name of Glanos or Glano, what the philosopher states concerning his Glanis agrees well enough with our Silouros, so far as we know its history; the disturbance that stormy weather causes him, the slow development of the eggs, their size, the care he takes of them, the noise he makes, &c.
“It is possible that at a certain period the name Silouros, which Aristotle does not employ, may not have been the synonyme of Glanis. For in a passage of Ælian, where the Glanis of the Strymon [misprinted in Cuvier's work Shymon] is mentioned, the Glanis of Aristotle is compared with the Silouros. Perhaps this name belonged originally to some of the species of Egypt or Syria ; but what is also very certain is, that, in another passage, Ælian applies this name to our Silouros of the Danube ; and Pliny makes the same application, and even employs it in translating the very passages of Aristotle.'*
* Aristotle, Hist. An., Lib. VI. c. xiii. 96 2-6. † Lib. IX. c. xxv. 6.
“What Aristotle relates in detail, and in two passages, of the care which the male Silourus takes of the eggs of the female, borders on the marvellous. According to him, the large Silouri deposit them in deep waters ; the smaller among the roots of willows and other trees, among the reeds or even the mosses. The female, having laid them, leaves them, but the male guards and defends them; and as the eggs are long in developing, he continues this care forty or fifty days.' +
“ Within the last ten years, much unexpected information has been collected by naturalists themselves, no longer borrowed from indirect observation, but ascertained while tracing their embryonic growth. Among these investigations, none has attracted so much attention as that of Coste, who observed that the Sticklebacks of Europe build a very neatly constructed nest, in which the eggs are deposited, the parents sitting upon and watching by them until the young are hatched. This fact, however, had already been noticed more than thirty years ago, and recorded in the Isis of Oken. Von Martens had made similar observations upon a species of Gobius, found in the Lagunes of Venice. But from want of sufficiently minute illustrations, these facts hardly attracted notice, until the full and extensive accounts of Coste, accompanied with numerous drawings, not only removed all doubt respecting the care which some fishes take of their progeny, but revived extensively the interest in such investigations.
“Since I have been in the United States, my attention has been par. ticularly directed to this subject, again and again, by the numerous reports which have reached me, that there are in this country several species of fishes which take care of their young in a similar way, belonging to the genera Catostomus, Exoglossum, Pomotis, and Pimelodus. Of Exoglossum and Catostomus I have had no opportunity thus far to observe the habits with sufficient minuteness to ascertain which of the numerous species of the latter genus takes such care of its young, and in what way this is performed; but it is reported of Exoglossum, that
* Cuvier, Histoire des Poissons, Liv. XVII. c. 1, Vol. XIV. pp. 344, 345. + Ibid. pp. 350, 351.
they carry little stones to build heaps, among which the eggs are laid; and this species is commonly called Stone-toters (carriers of stone). But I have had ample opportunity to watch the Pomotis in the breeding season every spring for the last eight years. At that time it approaches in pairs the shores of the ponds in which it lives, and selects shallow, gravelly places, overgrown with Potamogeton, water-lilies, and other aquatic plants, in which it begins by clearing a space of about a foot in diameter, rooting out the.plants, removing, with violent jerks of its tail, the larger pebbles, carrying away with its mouth the coarser gravel, and leaving a clean spot of fine sand, in which it deposits its eggs, surrounded and overshadowed by a grove of verdure as represented in the following wood-cut. In
this enclosure one of the parents remains hovering over its brood, and keeping at a distance all intruders. The office of watching over the progeny does not devolve exclusively upon either of the sexes, but the males and females keep watch alternately. The fierceness with which they dart at their enemies, and the anxiety with which they look out for every approaching danger, show that these are endowed with stronger instincts than have been known heretofore in any of their class. Their foresight goes so far as to avoid the bait attached to any hook, however near it may be brought to them, and however lively and tempting it may be. Pomotis do not build their nest singly ; hundreds of them may be seen along the same shore, within very small distances of one another, forming, as it were, temporary settlements, two nests sometimes hard by each other, or only separated by narrow partitions of water-plants. However near to one another, the pair of one nest do not interfere with those of another, VOL. III.
but like good neighbors they live peacefully together, passing over each other's domain when going out for food without making any disturbance. But whenever an unmated single fish makes its appearance among the nests, he is chased away like an intruding libertine and vagabond. The development of the egg is very rapid. In less than a week the young are hatched, and the parents soon cease to take any further care of them.
“ Pimelodus catus I have had fewer opportunities to watch. However, I have seen them in the spring, which, in the latitude they in. habit, does not fairly set in before the end of May, approach the shores of our ponds, like Pomotis, in pairs, and clear also a space among the low water-grasses, scirpus, and the like, in very shallow water, not more than a foot or so in depth, and deposit its eggs in the same manner as Pomotis, and watch as carefully and vigilantly over its progeny. Yet I have not been able to ascertain how long the period of incubation lasts. But at different times I have seen the young already hatched, still hanging about within the area of the nest, protected by their watchful parent: sometimes the male and female remaining together with them; at other times, either one or the other of the old fish keeping watch alone. I have seen larger broods of young, already three fourths of an inch, and even an inch long, remaining together like a flock, around one or the other of the parents ; and sometimes both swimming slowly in the centre or by the side of what, at some distance, would appear like a black cloud rolling slowly through the water in one or another direction, but which, seen more closely, proves to be a flock of young fish. I have observed such flocking broods through the whole month of June, and noticed that in each the young were of larger and larger size in the latter part of that month, until they swim more loosely, and finally disperse half together; the parents standing nearer the flock, or even in its centre, in proportion as the fish are smaller. When watching over the eggs which are not yet hatched, or when following the young brood, the old fish seem very solicitous for the safety of their progeny, and drive away with great fierceness any approaching enemy. I have even seen one dart at a little hand-net which I was dipping in the water, to secure the young which were still hovering over their nest.
Having thus far become familiar with the mode of reproduction of Pimelodus, the statements of Aristotle relating to the Glanis of Greece, which is another representative of the same family of Silu