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higher Vertebrata. In the lower classes they are of a much less complicated character. Thus in many fishes the concentric lamella do not exist, and therefore there has been no linear arrangement of the cartilage-cells. But these cells are ossified in situ, and their canaliculi, radiating thence on every side, give to the whole a most regular and beautiful appearance.

“ The cartilage of the cartilaginous fishes seems to differ from the common cartilage of the higher Vertebrata. In fact, it cannot be called true cartilage, but is, if I may so express myself, an, osseous tissue in a cartilaginous dress.

“ This may be explained by a few remarks. Valenciennes * has shown that the cartilage of the cartilaginous fishes and of the Cephalopoda contains gelatine, and not chondrine.

“ Müller † has also shown that all cartilage capable of ossification contains chondrine, and not gelatine, and that after ossification no chondrine is found, but all is gelatine. Therefore bones are, so to speak, gelatinous, and not chondrinous ; which, as we have just seen, is also true of the so-called cartilages of the cartilaginous fishes and Cephalopoda.

“ The tissue forming the skeleton of these fishes, as I have had opportunities to examine it, is composed of oval or spherical cells like those of common cartilage at an early period. They have become hardened in situ, but not calcarified; and never have I met any baving canaliculi radiating from them. From these data we may conclude that in these lower fishes there is bone-cartilage, but not true bone."

Professor Agassiz said that he believed naturalists, in considering organic tissues, were altogether too much in the habit of looking at different tissues as if they were entirely distinct bodies, forgetful of the fact that all are derived from one yolk. In considering the first formation of cartilage, we must look to the formation and development of the dorsal cord. We find these cells differing from the blastodermic cells, in being larger, but bearing no resemblance to cartilage-cells, although they form the basis from which the cartilage-cells are built up. He had carefully examined these cells, which, however, presented points of extreme difficulty, but had not

* Compt. Rend., Nov. 25, 1844.
† Poggendorff, Annalen, Band XXXVIII. p. 316.

yet succeeded in determining whether they were the identical ones which were to be transformed into cartilage-cells, or whether, on the other hand, they were the mother cells, from which the cartilaginous cells would derive their origin.

Mr. Agassiz further stated that he had examined the cartilage-like bones of fishes, of which Dr. Burnett had spoken, and that he had found the same results.

Professor Eustis gave an account of a formula for the measure of the solidity of a prismoid, and its application to other cases of menstration.

The ordinary formula for the area of a prismoid is į h (B +6+4 M), where B and b represent the areas of the upper and lower bases respectively, M the middle section, and h the height. The application of this formula for the mensuration of the sphere and the cone is alluded to in a recent number of the Journal of the Franklin Institute. But still more remarkable cases are those of the paraboloid, hyperboloid, and ellipsoid of revolution, in which the prismoidal formula will be found to give precisely the same results as those obtained by the application of the ordinary formulas from the calculus.

Professor Lovering exhibited a new stereoscope just received, and called the attention of the Academy to some points of detail, especially those arising from the difference of effect when the same drawings of a solid are viewed so as to represent it with one side or its opposite nearest to the eye.

Dr. Burnett commented on these facts, as demonstrating the proposition that the seat of vision is in the brain, and not in the retina.

Dr. B. A. Gould addressed some inquiries to Dr. Burnett concerning the best spider-lines for use in the micrometers of telescopes and microscopes.

A discussion ensued upon the qualities necessary in spiderlines for this purpose, in which Messrs. Burnett, Eustis, and Gould took part.

Dr. Burnett thought that the thread of the Attus or hunting spider was the most desirable in all respects, having almost

uniformly a diameter of just goto of an inch, and being wholly free from viscosity. The Attus is found at this season of the year on rail fences.

Professor Agassiz presented a paper upon the family of the Cyprinodonts.

Three hundred and seventieth meeting.

November 2, 1852. — Monthly Meeting. The President in the chair.

Professor Felton, reminded the Academy of the recent death of the Hon. Daniel Webster, Secretary of State of the United States, and Fellow of this body; and, after an eloquent tribute to his memory, offered the following resolutions, which, after being seconded by Mr. F. C. Gray, and advocated by Mr. Parsons, were unanimously adopted.

Resolved, That the Fellows of the American Academy of Arts and Sciences deeply lament the decease of their late Associate, the Hon. Daniel Webster, Secretary of State of the United States. By his death the country is bereaved of her ablest practical statesman, and profoundest political philosopher. Letters and eloquence have lost a most distinguished ornament. Science is deprived of a great and versatile mind, which understood its progress, appreciated its value, recognized its dignity, and mastered its results in the midst of professional labors and public cares, to which his energies were devoted almost to the last moment of his life.

Resolred, That the Fellows of this Academy tender to the family of their late eminent Associate, their most respectful sympathy in this private and public calamity.”

Three hundred and seventy-first meeting. November 10, 1852. — QUARTERLY MEETING. The President in the chair.

The Corresponding Secretary laid before the Academy letters from the Royal Society of London, and the Academies of Göttingen, Berlin, Vienna, and Munich, referring to publications forwarded to the Academy.

A communication from the Royal Society of Northern Antiqnaries in Copenhagen, containing circulars relating to the collection of materials for works upon the history of the Old Northern Literature, was laid before the Academy.

Dr. William P. Dexter was elected a Fellow of the Academy.

M. Brown Léquard, of Paris, personally made the following communication.

He stated that he had succeeded in producing muscular irritability, i. e. life in the muscles, after decomposition had commenced, by means of injections of blood, repeated every two or three hours. But the fact of which he wished to speak this evening was quite different. He had found that muscles separated from the body might be maintained in a state of rigidity by the injection of chloroform. After an interval of several days, blood might be again introduced, repelling the chloroform, and reinducing the irritability of the muscles. In one case, after the lapse of ten days, muscular life had been restored by the injection of blood, though the amount of blood required was much greater than after a smaller interval. Irritability might also sometimes be introtroduced, though more rarely.

In reply to a question of Dr. Pickering, M. Léquard stated that the blood must be as fresh as possible, though it was capable of producing the effect when an hour old. In one case in Paris, he had found that blood which had been drawn for two hours had sufficed.

With regard to the proper kind of blood for transfusion, he had found that fibrine was not necessary, so that the operation can be performed with defibrinated blood. Bischoff had discovered, that, in those cases where the blood of one animal was poison to another, this quality was due solely to the fibrine, so that defibrinated blood may be used in all cases for transfusion without deleterious results. There is another interesting fact, namely, that animals have more fibrine in their blood when they have not been fed for a long time, than under ordinary circumstances.

Dr. Samuel Kneeland was elected Recording Secretary, in place of Dr. B. A. Gould, who resigned.

Three hundred and seventy-second meeting.

December 7, 1852. — MONTHLY MEETING. The President in the chair.

Professor Winlock, of Kentucky, made a verbal report on errors he had discovered in Bradley's and Bessel's Observations on the sun, illustrated by diagrams.

Professor Peirce observed that this was a very remarkable application of the method of least squares, leading to the discovery of such a small difference between the printed observations and the true result. He gave other examples of the detection of errors by the application of this method, showing that even errors are regulated by laws. He remarked, that, with all our accuracy, the diameter of the sun is not yet known; the best way to ascertain this is by an eclipse, but even this is open to doubts.

Professor Peirce alluded to several errors attributed to him in some foreign journals; - the idea that the orbit of the comet of 1689 was the same as that of 1843 had been erroneously attributed to him. He believed also that astronomers will yet acknowledge that there are two solutions to the perturbing actions of Neptune on Uranus.

Dr. J. Wyman offered some remarks on the internal structure of the cranium of the mastodon. He had compared the foramina through which the nerves escape from the cranial cavity with those in the skull of the elephant; those transmitting the trigeminus and facial nerves were of similar proportions in the two, and tended to show that the mastodon, as well as the elephant, was provided with a trunk, the large size of the nerves indicating a corresponding development of muscular fibre and of sensitive surface in the face.

The form of the cranial cavity, which has not been described, corresponded with the extraordinary type met with in

VOL. 111.

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