Page:Encyclopædia Britannica, Ninth Edition, v. 18.djvu/40

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30 in certain groups the number of " primaries," or quill-feathers grow ing from the mantis or distal segment of the wing, formed another characteristic easy of observation. In the Oscincs or Pohjmyodi of Miiller the number was either nine or ten and if the latter the outermost of them was generally very small. In tvo of the other groups of which Prof. Cabanis especially treated groups which hail been hitherto more or less confounded with the Oscincs the number of primaries was invariably ten, and the outermost of them was comparatively large. This observation was also hailed as the dis covery of a fact of extraordinary importance ; ami, from the results of these investigations, taken altogether, Ornithology was declared by Sundevall, undoubtedly a man who had a right to speak with authority, to have made greater progress than had been achieved since the, days of Cuvier. The final disposition of the " Subclass Inscssores" all the perching Birds, that is to say, which are neither Birds-of-Prey nor Pigeons proposed by Prof. Cabanis, was into four " Orders," as follows : 1. Oscines, equal to Miiller s group of the same name ; 2. Clamatorcs, being a majority of that division of the Picariie of Nitzsch, so called by Andreas Wagner, in 1841, 1 which have their feet normally constructed ; 3. Strisorcs, a group now separated from the Clamatorcs of Wagner, and containing those forms which have their feet abnor mally constructed ; and 4. Scansorcs, being the Grimpeurs of Cuvier, the Zygodadyli of several other systematists. The first of these four " Orders " had been already indefensibly 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, Clamatorcs, 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. Yet even then enough had been ascertained to have saved what are now recognized as the Families Todidse, and Tyrannidse, from being placed as " Subfamilies" in the same " Family Coloptcridse" ; and several other instances of unharmonious combination in this "Order" might be adduced were it worth while to particularize them. More than that, it would not be difficult to shew, only the present is not exactly the place for it, that some groups or Families which in reality are not far distant from one another are distributed, owing to the dissimilarity of their external characters, throughout these three Orders. Thus the Podarginse are associated with the Coradidie under the head Clnmatorcs, while the Caprimulyidae, to which they are clearly most allied, if they do not form part of that Family (GOATSUCKER, vol. x. p. 711), are placed with the Strisorcs ; and again the Mu&ophogidse also stand as Strisorcs, while the Cucnlidse, which modern systematists think to be their nearest relations, are considered to be Scansores. But to return to the Oscines, the arrangement of which in the classification now under review has been deemed its greatest merit, and consequently has been very generally followed. That by virtue of the perfection of their vocal organs, and certain other properties though some of these last have perhaps never yet been made clear enough they should stand at the head of the whole Class, may here be freely admitted, but the respective rank assigned to the various component Families of the group is certainly open to question, and to the present writer seems, in the methods of several systematists, to be based upon a fallacy. This respective rank of the different Families appears to have been assigned on the principle that, since by reason of one character (namely, the more complicated structure of their syrinx) the Oscines form a higher group than the Clamatsires, therefore all the concomitant features which the former possess and the latter do not must be equally indicative of superiority. Now one of the features in which most of the Oscines differ from the lower " Order " is the having a more or less undivided planta, and accord ingly it has been assumed that the Family of Oscines in which this modification of the planta is carried to its extreme point must be the highest of that "Order." Since, therefore, this extreme modification of the planta is 1 Archiv fur Xaturgeschichte, vii. 2, pp. 93, 94. The division seems to have been instituted by this author a couple of years earlier in the second edition of his Handbuch der Naturyeschichte (a work not seen by the present writer), but not then to have received a scientific name. It included all Picariie which had not " xygodacty- lous " feet, that is to say, toes placed in pairs, two before and two behind. exhibited by the Thrushes and their allies, it is alleged that they must be placed first, and indeed at the head of all Birds. The groundlessness of this reasoning ought to be apparent to everybody. In the present state of anatomy at any rate, it is impossible to prove that there is more than a coincidence in the facts just stated, and in the association of two characters one deeply seated and affecting the whole life of the Bird, the other superficially, and so far as we can perceive without effect upon its organism. Because the Clamutores^ having no song- muscles, have a divided planta, it cannot be logical to assume that among the Oscines, which possess song-muscles, such of them as have an undivided planta must be higher than those that have it divided. The argument, if it can be called an argument, is hardly one of analogy; and yet no stronger ground has been occupied by those who invest the Thrushes, as do the majority of modern systematists, with the most dignified position in the whole Class. But passing from general to particular considerations, so soon as a practical application of the principle is made its inefficacy is manifest. The test of perfection of the vocal organs must be the perfection of the notes they enable their possessor to utter. There cannot be a question that, sing admirably as do some of the Birds included among the Thrushes, 2 the Larks, as a Family, infinitely surpass them. Yet the Larks form the very group which, as has been already shewn (LAKK, vol. xiv. p. 314), have the planta more divided than any other among the Oscines. It seems hardly possible to adduce anything that would more conclusively demonstrate the independent nature of each of these characters the complicated structure of the syrinx and the asserted inferior formation of the planta which are in the Alaiididx associated. 3 Moreover, this same Family affords a very valid protest against the extreme value attached to the presence or absence of the outermost quill-feather of the wings, and in this work it has been before shewn (vt svpra) that almost every stage of magnitude in this feather is exhibited by the Larks from its rudimentary or almost abortive condition in Alavda arvensis to its very considerable development in Mefano- corypha calandra. Indeed there are many genera of Oscines in which the proportion that the outermost primary bears to the rest is at best but a specific character, and certain exceptions are allowed by Prof. Cabanis (p. 313) to exist. Some of them it is now easy to explain, inas much as in a few cases the apparently aberrant genera have elsewhere found a more natural position, a contin gency to which he himself was fully awake. But as a rule the allocation and ranking of the different Families of Oscines by this author must be deemed arbitrary. 4 Yet the value of his Ornithologische Notizen is great, not only as evidence of his extraordinarily extensive acquaintance with different forms, which is proclaimed in every page, but in leading to a far fuller appreciation of characters that certainly should on no account be neglected, though - Prof. Cabanis would have strengthened his position had he included in the same Family with the Thrushes, which lie called Rha- cnemidse, the Birds commonly known as Warblers, Sylviidw, which the more advanced of recent systematists are inclined with much reason to unite with the Thrushes, Turdidse ; but instead of that he, trusting to the plantar character, segregated the Warblers, including of course the Nightingale, and did not even allow them the second place in his method, putting them below the Family called by him Sylvicolidse, consisting chiefly of the American forms now known as Mniotiltidie,, none of which as songsters approach those of the Old World. 3 It must be observed that Prof. Cabanis does not place the Alaudidss lowest of the seventeen Families of which he makes the Oscines to be composed. They stand eleventh in order, while the Corvidas are last a matter on which something has to be said in the sequel. 4 By a curious error, probably of the press, the number of primaries assigned to the Paradiseid.se and Con^idse. is wrong (pp. 334, 335). In each case 10 should be substituted for 19 and 14.