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Show 1878.] MR. D. G. ELLIOT ON THE GENUS PTILOPUS. 509 in the family. Some authors have separated them from the rest of the Pigeons on account of the abruptly attenuated first primary. This is utterly worthless, either as a generic or a specific character, as among the species which are included in Ptilopus every gradation of the first primary is procurable, from the most abrupt attenuation to the normal shape of feather. I here give (fig. 1), in proof of this assertion, a series of drawings of first primaries, together with the name of the species to which each belongs, so that any one can verify it for himself; and I may state that it would not have been at all difficult to have arranged a more minute gradation from the species at m y disposal if it had been necessary; but those given will be found, I think, amply sufficient for the purpose. Another so-called character, which has been adopted by some to distinguish the members of the genus Ptilopus, and one which is expressed by the term itself, is the tarsus feathered to the foot. This proves to be of no more value, generically or specifically, than the attenuated primary. Species with or without the last-named character have the tarsus covered or partly bare, as do also those with the graduated or normal shape of this feather. The drawings (pp. 510, 511) of the partly bare and partly covered tarsus, together with the first primary of several species, will show clearly how very unsatisfactory these characters are. Relative lengths of wing and tail, as given by some writers for the separation of some of these birds into different genera, also are not constant, as tbe tail can be found shorter than the wing, or nearly equal to it in length. This last is the main character given by Reichen-bach for separating the birds placed by him in his genus Meqalopre-pia, as all the others are common to different species of Ptilopus. H e says:-" Schwanz fast so lang wie die Fliigel. Vorderschwinge nicht verschmalert." The species included by him, it is true, have not this last character; but Pt. perlatus has the tail only a little over half the length of the wing, while Pt. cinctus and Pt. gularis, neither of which are included in Megaloprepia, have the tail nearly as long as the wing, with the first primary abruptly attenuated. I do not see that there is a single character remaining among those given by Reichenbach which can distinguish the birds included in his genus from those of the genus Ptilopus. For those who deem colour sufficient to establish a genus, it might be supposed that among these gaily plumaged birds certain patterns might be found which would answer for a generic character. But this, again, fails; for the variety of the coloration is so great that it would be necessary to divide the group into numerous genera (as has, indeed, been attempted), and many of the species would be left alone to represent a genus. I do not find any thing better to designate the genus than the following formula:- Ptilopus. Size moderate; wings usually reaching two thirds the length of the tail; rectrices fourteen in number, excepting Pt. occipitalis, which has apparently sixteen ; tarsi partly or wholly covered with feathers ; colours of plumage usually bright, and often strongly |