ornithology, as might be expected from such a man as he was, placed the Pterylographie at the summit of those publications the appearance of which he had to record for the years 1839 and 1840, stating that for “Systematik,” it was of the greatest importance.[1] On the other hand Oken (Isis, 1842, pp. 391-394), though giving a summary of Nitzsch's results and classification, was more sparing of his praise, and prefaced his remarks by asserting that he could not refrain from laughter when he looked at the plates in Nitzsch's work, since they reminded him of the plucked fowls hanging in a poulterer's shop, and goes on to say that, as the author always had the luck to engage in researches of which nobody thought, so had he the luck to print them where nobody sought them. In Sweden Sundevall, without accepting Nitzsch's views, accorded them a far more appreciative greeting in his annual reports for 1840-1842 (i. pp. 152-160); but, of course, in England and France[2] nothing was known of them beyond the scantiest notice, generally taken at second hand, in two or three publications. Thanks to Mr Sclater, the Ray Society was induced to publish, in 1867, an excellent translation by Mr Dallas of Nitzsch's Pterylography, and thereby, however tardily, justice was at length rendered by British ornithologists to one of their greatest foreign brethren.[3] Nitzsch's work on feathers has been carried farther by many later observers, and its value is now generally accepted (see Feather).
The treatise of Kessler on the osteology of birds' feet, published in the Bulletin of the Moscow Society of Naturalists for 1841, next Kessler. claims a few words, though its scope is rather to show differences than affinities; but treatment of that kind is undoubtedly useful at times in indicating that alliances generally admitted are unnatural; and this is the case here, for, following Calvier's method, the author's researches prove the artificial character of some of its associations. While furnishing—almost unconsciously, however—additional evidence for overthrowing that classification, there is, nevertheless, no attempt made to construct a better one; and the elaborate tables of dimensions, both absolute and proportional, suggestive as is the whole tendency of the author's observations, seem not to lead to any very practical result, though the systematist's need to look beneath the integument, even in parts that are so comparatively little hidden as birds' feet, is once more made beyond all question apparent.
It has already been mentioned that Macgillivray contributed to Audubon's Ornithological Biography a series of descriptions of Macgillivray and Audubon. some parts of the anatomy of American birds, from subjects supplied to him by that enthusiastic naturalist, whose zeal and prescience, it may be called, in this respect merits all praise. Thus he (prompted very likely by Macgillivray) wrote: “I believe the time to be approaching when much of the results obtained from the inspection of the exterior alone will be laid aside; when museums filled with stuffed skins will be considered insufficient to afford a knowledge of birds; and when the student will go forth, not only to observe the habits and haunts of animals, but to preserve specimens of them to be carefully dissected” (Ornith. Biography, iv., Introduction, p. xxiv). As has been stated, the first of this series of anatomical descriptions appeared in the fourth volume of his work, published in 1838, but they were continued until its completion with the fifth volume in the following year, and the whole was incorporated into what may be termed its second edition, The Birds of America, which appeared between 1840 and 1844. Among the many species whose anatomy Macgillivray thus partly described from autopsy were at least half a dozen[4] of those now referred to the family Tyrannidae (see King Bird), but then included, with many others, according to the irrational, vague and rudimentary notions of classification of the time, in what was termed the family “Muscicapinae.” In all these species he found the vocal organs to differ essentially in structure from those of other birds of the Old World, which we now call Passerine, or, to be still more precise, Oscinian. But by him these last were most arbitrarily severed, dissociated from their allies, and wrongly combined with other forms by no means nearly related to them (Brit. Birds, i. pp. 17, 18) which he also examined; and he practically, though not literally,[5] asserted the truth, when he said that the general structure, but especially the muscular appendages, of the lower larynx was “similarly formed in all other birds of this family” described in Audubon's work. Macgillivray did not, however, assign to this essential difference any systematic value. Indeed he was so much prepossessed in favour of a classification based on the structure of the digestive organs that he could not bring himself to consider vocal muscles to be of much taxonomic use, and it was reserved Johannes Müller. to Johannes Müller to point out that the contrary was the fact. This the great German comparative anatomist did in two communications to the Academy of Sciences of Berlin, one on the 26th June 1845 and the other on the 14th May 1846, which, having been first briefly published in the Academy's Monatsbericht, were afterwards printed in full, and illustrated by numerous figures, in its Abhandlungen, though in this latter and complete form they did not appear in public until 1847. This very remarkable treatise forms the groundwork of almost all later or recent researches in the comparative anatomy and consequent arrangement of the Passeres, and, though it is certainly not free from inperfections, many of them, it must be said, arise from want of material, notwithstanding that its author had command of a much more abundant supply than was at the disposal of Nitzsch. Carrying on the work from the anatomical point at which he had left it, correcting his errors, and utilizing to the fullest extent the observations of Keyserling and Blasius, to which reference has already been made, Müller, though hampered by mistaken notions of which he seems to have been unable to rid himself, propounded a scheme for the classification of this group, the general truth of which has been admitted by all his successors, based, as the title of his treatise expressed, on the hitherto unknown different types of the vocal organs in the Passerines. He freely recognized the prior discoveries of, as he thought, Audubon, though really, as has since been ascertained, of Macgillivray; but Müller was able to perceive their systematic value, which Macgillivray did not, and taught others to know it. At the same time Müller showed himself, his power of discrimination notwithstanding, to fall behind Nitzsch in one very crucial point, for he refused to the latter's Picariae the rank that had been claimed for them, and imagined that the groups associated under that name formed but a third “tribe”—Picarii—of a great order Insessores, the others being (1) the Oscines or Polymyodi—the singing birds by emphasis, whose inferior larynx was endowed with the full number of five pairs of song-muscles, and (2) the Tracheophones, composed of some South-American families. Looking on Müller's labours as we now can, we see that such errors as he committed are chiefly due to his want of special knowledge of ornithology, combined with the absence in several instances of sufficient materials for investigation. Nothing whatever is to be said against the composition of his first and second “tribes”; but the third is an assemblage still more heterogeneous than that which Nitzsch brought together under a name so like that of Müller—for the fact must never be allowed to go out of sight that the extent of the Picarii of the latter is not at all that of the Picariae of the former.[6] For
- ↑ Archiv für Naturgeschichte, vii. 2, pp. 60, 61.
- ↑ In 1836 Jacquemin communicated to the French Academy (Comptes rendus, ii. pp. 374, 375 and 472) some observations on the order in which feathers are disposed on the body of birds; but, however general may have been the scope of his investigations, the portion of them published refers only to the crow, and there is no mention made of Nitzsch's former work.
- ↑ The Ray Society had the good fortune to obtain the ten original copper-plates, all but one drawn by the author himself, wherewith the work was illustrated. It is only to be regretted that the Society did not also adopt the quarto size in which it appeared, for by issuing their English version in folio they needlessly put an impediment in the way of its common and convenient use.
- ↑ These are, according to modern nomenclature, Tyrannus carolinensis and (as before mentioned) T. verticalis, Myiarchus crinitus, Sayornis fuscus, Contopus virens and Empidonax acadicus.
- ↑ Not literally, because a few other forms such as the genera Polioptila and Ptilogonys, now known to have no relation to the Tyrannidae, were included, though these forms, it would seem, had never been dissected by him. On the other hand, he declares that the American redstart, Muscicapa, or, as it now stands, Setophaga ruticilla, when young, has its vocal organs like the rest—an extraordinary statement which is worthy the attention of the many able American ornithologists.
- ↑ It is not needless to point out this fine distinction, for more than one modern author would seem to have overlooked it.
