Page:Encyclopædia Britannica, Ninth Edition, v. 18.djvu/33

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K NITHOLOGY 23 his time, right enough and somewhat instructive. It was only when, after a close examination of the sternal apparatus of one hundred and thirty species, which he carefully described, that he arrived (pp. 177-183) at the conclusion astonishing to us who know of L Herminier s previous results that the sternum of Birds cannot be used as a help to their classification on account of the egregious anomalies that would follow the proceeding such anomalies, for instance, as the separation of Cypsclus from Birundo and its alliance with Trochilus, and the grouping of Hiruntlo and Fringilla together. He seems to have been persuaded that the method of Linnojus and his disciples was indisputably right, and that any method which contradicted it must therefore be wrong. Moreover, he appears to have regarded the sternal structure as a mere function of the Bird s habit, especially in regard to its power of flight, and to have wholly overlooked the converse position that this power of flight must depend entirely on tho structure. Good descriptive anatomist as he certainly was, he was false to the anatomist s creed; but it is plain, from reading his careful descriptions of sternurns, that he could not grasp the essential characters he had before him, and, attracted only by the more salient and obvious features, had not capacity to interpret the me ining of the whole. Yet he did not amiss by giving many figures of stern urns hitherto unrepresented. We pass from him to a more lively theme. At the very beginning of the year 1832 Cuvier laid before the Academy of Sciences of Paris a memoir on the progress of ossification in the sternum of Birds, of which memoir an abstract will be found in the Ann r des des Sciences Naturelles (xxv. pp. 260-272). Herein he treated of several subjects with which we are not particularly con cerned at present, and his remarks throughout were chiefly directed against certain theories which F^tienne Geoffroy St-Hilaire had propounded in his Philosophic Anatomique, published a good many years before, and need not trouble us here ; but what does signify to us now is that Cuvier traced in detail, illustrating his statements by the preparations he exhibited, the progress of ossification in the sternum of the Fowl and of the Duck, pointing out how it differed in each, and giving his interpretation of the differ ences. It had hitherto been generally believed that the mode of ossification in the Fowl was that which obtained in all Birds the Ostrich and its allies (as L Herminier, we have seen, had already shewn) excepted. But it was now made to appear that the Struthi- ous Birds in this respect resembled, not only the Duck, but a great many other groups Waders, Birds-of-Prey, Pigeons, Passerines, and perhaps all Birds not Galli naceous, so that, according to Cuvier s view, the five points of ossification observed in the Gallinx, instead of exhibiting the normal process, exhibited one quite exceptional, and that in all other Birds, so far as he had been enabled to investigate the matter, ossification of the sternum began at two points only, situated near the anterior upper margin of the side of the sternum, and gradually crept towards the keel, into which it presently extended ; and, though he allowed the appearance of detached portions of calcareous matter at the base of the still cartilaginous keel in Ducks at a certain age, he seemed to consider this an individual peculiarity. This fact was fastened upon by Geoffroy in his reply, which was a week later presented to the Academy, but was not published in full until the following year, when it appeared in the Annales du Museum (ser. 3, ii. pp. 1-22). Geoffroy here maintained that the five centres of ossification existed in the Duck just as in the Fowl, and that the real difference of the process lay in the period at which they made their appearance, a circumstance, which, though virtually proved by the preparations Cuvier had used, had been by him overlooked or misinterpreted. The Fowl possesses all five ossifications at birth, and for a long while the middle piece forming the keel is by far the largest. They all grow slowly, and it is not until the animal is about six months old that they are united into one firm bone. The Duck on the other hand, when newly hatched, and for nearly a month after, has the sternum wholly cartilaginous. Then, it is true, two lateral points of ossification appear at the margin, but subsequently the remaining three are developed, and when once formed they grow with much greater rapidity than in the Fowl, so that by the time the young Duck is quite independent of its parents, and can shift for itself, the whole sternum is completely bony. Nor, argued Geoffroy, was it true to say, as Cuvier had said, that the like occurred in the Pigeons and true Passerines. In their case the sternum begins to ossify from three very distinct points one of which is the centre of ossification of the keel. As regards the Struthious Birds, they could not be likened to the Duck, for in them at no age was there any indication of a single median centre of ossification, as Geoffroy had satisfied himself by his own observations made in Egypt many years before. Cuvier seems to have acquiesced in the corrections of his views made by Geoffroy, and attempted no rejoinder ; but the attentive and impartial student of the discussion will see that a good deal was really wanting to make the latter s reply effective, though, as events have shewn, the former was hasty in the conclusions at which he arrived, having trusted too much to the first appearance of centres of ossification, for, had his observations in regard to other Birds been carried on with the same attention to detail as in regard to the Fowl, he would certainly have reached some very different results. In 1834 GLOGER brought out at Breslau the first (and unfortu- Gloger. nately the only) part of a V ollstandiyes Handbuch dcr Natur- //cschichte der Vogd Europas, treating of the Land-birds. In the introduction to this book (p. xxxviii., note) he expressed his regret at not being able to use as fully as he could wish the excellent researches of Xitzsch which were then appearing (as has been above said) in the successive parts of Naumann s great work. Notwith standing this, to Gloger seems to belong the credit of being the first author to avail himself in a book intended for practical ornitho logists of the new light that had already been shed on Systematic Ornithology ; and accordingly we have the second Order of his arrangement, the Arcs Passerine, divided into two Suborders : Singing Passerines (meloditsze), and Passerines without an apparatus of Song-muscles (anomalas) the latter including what some later writers called Picariss. For the rest his classification demands no particular remark ; but that in a work of this kind he had the courage to recognize, for instance, such a fact as the essential difference between Swallows and Swifts lifts him considerably above the crowd of other ornithological writers of his time. An improvement on tiie old method of classification by purely external characters was introduced to the Academy of Sciences of Stockholm by SUNDKVALL in 1835, and was published the following Sunde- year iu its Handlingnr (pp. 43-130). This was the foundation of vail, a more extensive work of which, from the influence it still exerts, it will be necessary to treat later at some length, and there will be no need now to enter much into details respecting the earlier per formance. It is sufficient here to remark that the author, even then a man of great erudition, must have been aware of the turn which taxonomy was taking ; but, not being able to divest himself of the older notion that external characters were superior to those fur nished by the study of internal structure, and that Comparative Anatomy, instead of being a part of Zoology, was something dis tinct from it, he seems to have endeavoured to form a scheme which, while not running wholly counter to the teachings of Comparative Anatomists, should yet rest ostensibly on external characters. With this view he studied the latter most laboriously, and in some measure certainly not without success, for he brought into promin ence several points that had hitherto escaped the notice of his pre decessors. He also admitted among his characteristics a physio logical consideration (apparently derived from Oken 1 ) dividing the class Arcs into two sections Altriccs and Preecocas, according as the young were fed by their parents or, from the first, fed themselves. But at this time he was encumbered with the hazy doctrine of analogies, which, if it did not act to his detriment, was assuredly of no service to him. He prefixed an "Idea Systematis" to his "Expositio"; and the former, which appears to represent his real opinion, differs in arrangement very considerably from the latter. Like Gloger, Sundevall in his ideal system separated the true Passerines from all other Birds, calling them Volucrcs ; but he took a step further, for he assigned to them the highest rank, wherein 1 He says from Oken s NnturrjcschicMe far Schulen, published in 1821, but the division is to be found in that author s earlier Lehrbuch der Zoologie (ii. p. 371), which appeared in 1816.