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Rh perching birds, that is to say, which are neither birds of prey nor pigeons—proposed by Professor Cabanis, was into four “Orders,” as follows:—

1. Oscines, equal to Müller’s group of the same name;

2. Clamatores, being a majority of that division of the Picariae of Nitzsch, so called by Andreas Wagner, in 1841, which have their feet normally constructed;

3. Strisores, a group now separated from the Clamatores of Wagner, and containing those forms which have their feet abnormally constructed; and

4. Scansores, being the Grimpeurs of Cuvier, the Zygodactyli of several other systematists.

The first of these four “Orders” had been already indefeasibly established as one perfectly natural, but respecting its details more must presently be said. The remaining three are now seen to be obviously artificial associations, and the second of them, Clamatores, in particular, containing a very heterogeneous assemblage of forms; but it must be borne in mind that the internal structure of some of them was at that time still more imperfectly known than now.

This will perhaps be the most convenient place to mention another kind of classification of birds, which, based on a principle wholly different from those that have just been explained, requires a few words, though it has not been productive, nor is likely, from all that appears, to be productive of any great effect. So long ago as 1831, Prince C. L. Bonaparte, in

his Saggio di una distribuzione metodica degli Animali Vertebrati, published at Rome, and in 1837 communicated to the Linnean Society of London, “A new Systematic Arrangement of Vertebrated Animals,” which was subsequently printed in that Society’s Transactions (xviii. pp. 247-304), though before it appeared there was issued at Bologna, under the title of Synopsis Vertebratorum Systematis, a Latin translation of it. Herein he divided the class Aves into two subclasses, to which he applied the names of Insessores and Grallatores (hitherto used by their inventors Vigors and Illiger in a different sense), in the latter work relying chiefly for this division on characters which had not before been used by any systematist, namely that in the former group monogamy generally prevailed and the helpless nestlings were fed by their parents, while the latter group were mostly polygamous, and the chicks at birth were active and capable of feeding themselves. This method, which in process of time was dignified by the title of a Physiological Arrangement, was insisted upon with more or less pertinacity by the author throughout a long series of publications, some of them separate books, some of them contributed to the memoirs issued by many scientific bodies of various European countries, ceasing only at his death, which in July 1857 found him occupied upon a Conspectus Generum Avium, that in consequence remains unfinished. In the course of this series, however, he saw fit to alter the name of his two subclasses, since those which he at first adopted were open to a variety of meanings, and in communication to the French Academy of Sciences in 1853 (Comptes rendus, xxxvii. pp. 641-647) the denomination Insessores was changed to Altrices, and Grallatores to Praecoces—the terms now preferred by him being taken from Sundevall’s treatise of 1835 already mentioned. The views of Bonaparte were, it appears, also shared by an ornithological amateur

of some distinction, John Hogg, who propounded a scheme which, as he subsequently stated (Zoologist, 1850, p. 2797), was founded strictly in accordance with them; but it would seem that, allowing his convictions to be warped by other considerations, he abandoned the original “physiological” basis of his system, so that this, when published in 1846 (Edinb. N. Philosoph. Journal, xli. pp. 50-71), was found to be established on a single character of the feet only; though he was careful to point out, immediately after formulating the definition of his subclasses Constrictipedes and Inconstrictipedes, that the former “make, in general, compact and well-built nests, wherein they bring up their very weak, blind, and mostly naked young, which they feed with care, by bringing food to them for many days, until they are fledged and sufficiently strong to leave their nest,” observing also that they “are principally monogamous” (pp. 55, 56); while of the latter he says that they “make either a poor and rude nest, in which they lay their eggs, or else none, depositing them on the bare ground. The young are generally born with their full sight, covered with down, strong, and capable of running or swimming immediately after they leave the egg-shell.” He adds that the parents, which “are mostly polygamous,” attend their young and direct them where to find their food (p. 63). The numerous errors in these assertions hardly need pointing out. The herons, for instance, are much more “Constrictipedes” than are the larks or the kingfishers, and, so far from the majority of “Inconstrictipedes” being polygamous, there is scarcely any evidence of polygamy obtaining as a habit among birds in a state of nature except in certain of the Gallinae and a very few others. Furthermore, the young of the goatsuckers are

at hatching far more developed than are those of the herons or the cormorants; and, in a general way, nearly every one of the asserted peculiarities of the two subclasses breaks down under careful examination. Yet the idea of a “physiological” arrangement on the same kind of principle found another follower, or, as he thought,

inventor, in Edward Newman, who in 1850 communicated to the Zoological Society of London a plan published in its Proceedings for that year (pp. 46-48), and reprinted also in his own journal The Zoologist (pp. 2780-2782), based on exactly the same considerations, dividing birds into two groups, “Hesthogenous”—a word so vicious in formation as to be incapable of amendment, but intended to signify those that were hatched with a clothing of down—and “Gymnogenous,” or those that were hatched naked. These three systems are essentially identical; but, plausible as they may be at the first aspect, they have been found to be practically useless, though such of their characters as their upholders have advanced with truth deserve attention. Physiology may one day very likely assist the systematist; but it must be real physiology and not a sham.

In 1856 Paul Gervais, who had already contributed to the Zoologie of M. de Castelnau’s Expédition dans les parties centrales de l’Amérique du Sud some important memoirs describing the anatomy of the hoactzin and certain other birds of doubtful or anomalous position, published some remarks on the characters which could be drawn from the sternum of birds (Ann. Sc. Nat. Zoologie, ser. 4, vi. pp. 5-15).

The considerations are not very striking from a general point of view; but the author adds to the weight of evidence which some of his predecessors had brought to bear on certain matters, particularly in aiding to abolish the artificial groups “Déodactyls,” “Syndactyls,” and “Zygodactyls,” on which so much reliance had been placed by many of his countrymen; and it is with him a great merit that he was the first apparently to recognize publicly that characters drawn from the posterior part of the sternum, and particularly from the “échancrures,” commonly called in English “notches” or “emarginations,” are of comparatively little importance, since their number is apt to vary in forms that are most closely allied, and even in species that are usually associated in the same genus or unquestionably belong to the same family, while these “notches” sometimes become simple foramina, as in certain pigeons, or on the other hand foramina may exceptionally change to “notches,” and not unfrequently disappear wholly. Among his chief systematic determinations we may mention that he refers the tinamous to the rails, because apparently of their deep “notches,” but otherwise takes a view of that group more correct according to modern notions than did most of his contemporaries. The bustards he would place with the “Limicoles,” as also Dromas and Chionis, the (q.v.). Phaethon, the (q.v.), he would place with the “Laridés” and not with the “Pelécanides,” which it only resembles in its feet having all the toes connected by a web. Finally divers, auks and penguins, according to him, form the last term in the series, and it seems fit to him that they should be regarded as forming a separate order. It is a curious fact that even at a date so late as this, and by an investigator so well informed, doubt should still have existed whether Apteryx (see ) should be referred to the group containing the cassowary and the ostrich. On the whole the remarks of this esteemed author do not go much beyond such as might occur to any one who had made a study of a good series of specimens; but many of them are published for the first time, and the author is careful to insist on the necessity of not resting solely on sternal characters, but associating with them those drawn from other parts of the body.

Three years later in the same journal (xi. 11-145, pls. 2-4) M. Blanchard published some Recherches sur les caractères ostéologiques des oiseaux appliquées à la classification naturelle de ces animaux, strongly urging the superiority of such characters over those drawn from the bill or feet, which, he remarks, though they may have sometimes given correct notions,

have mostly led to mistakes, and, if observations of habits and food have sometimes afforded happy results, they have often been deceptive; so that, should more be wanted than to draw up a mere inventory of creation or trace the distinctive outline of each species, zoology without anatomy would remain a barren study. At the same time he states that authors who have occupied themselves with the sternum alone have often produced uncertain results, especially when they have neglected its anterior for its posterior part; for in truth every bone of the skeleton ought to be studied in all its details. Yet this distinguished zoologist selects the sternum as furnishing the key to his primary groups or “Orders” of the class, adopting, as Merrem had done long before, the same two divisions Carinatae and Ratitae, naming, however, the former Tropidosternii and the latter Homalosternii. Some unkind fate has hitherto hindered