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Show 388 MR. F. E. BEDDARD OX THE TONGUE [Dec. 1, and there are traces of these, perhaps reduced to one spine, in Cathartes. I cannot, however, with any confidence distinguish the tongues of the two genera. The point, however, which I wish to emphasise is that this single inner spine, if there be only one, which lies medianly of the lateral fringing row, is the vestige of the V-shaped edging of spines which borders the tongue of other Accipitres posteriorly. The tongue of the Carthartidse, therefore, differs from that of other Accipitres in the nearly complete disappearance of the spines which border the tongue posteriorly, and the hypertrophy of the lateral spines which are indicated in some Accipitres, particularly in Vultur. I may remark finally that the numerous large glandular orifices (figured by Gadow) which are scattered over the tongue in Gypagus and Cathartes are not found in Vultur; nor is the slit of the glottis in the latter edged with spines as it is in the Cathartidse. In m y work* upon the anatomy of Birds, I briefly drew attention to the fact that the "syrinx" in the American Yultures presents two types-one characterising Cathartes, and the other the two genera Gypagus and Sarcorhamphus. I take the opportunity of expanding that account. In remarking that the Cathartidse are distinguished by their completely closed bronchial rings, I take it that Prof. Fiirbringer had in view the genus Cathartes only. It is only Cathartes that figures in the description of the muscular anatomy of Birds contained in his great work. In supporting Dr. Fiiibringer's statement, I found it necessaryf to limit that statement to Cathartes, since in Gypagus and Sarcorhamphus the bronchial " rings" are in reality semirings, as in birds with a tracheo-bronchial syrinx. The actual difference, however, between Cathartes and the other types is one of degree. In Cathartes the bulk of the bronchial cartilages are complete rings, while a few at the end (I counted five of these in two specimens selected at random) are semirings. In Gypagus, on the other hand, all the bronchial cartilages are semirings. In this point Gypagus agrees with Sarcorhamphus. A further peculiarity is noteworthy as distinctive of the several genera of Cathartidae with which I deal in the present communication, In Sarcorhamphus I have figured % the membrana tj^mpaniformis as continued upwards along the trachea posteriorly, which results, therefore, in the production of tracheal semirings. This longitudinal fissure of the tracheal rings exists for some distance. In Gypagus precisely the same state of affairs is to be found, only it is less extensive than in the Condor. I can find no trace of any transverse break in the tracheal rings of Cathartes. I have been able to examine four individuals which include both sexes. If it occurs, the probabilities are in favour of its being exceptional. W e have, therefore, in the structure of the -windpipe in these American Yultures two distinct types-one developed in Cathartes, and the other in Sarcorhamphus and Gypagus. '* 'The Structure and Classification of Birds,' London. 1808. + Loc. rif„ sec also " O n tin- Windpipe and Heart of the Condor," P. Z. S, 1902. vol. i, l>, 239. + P, Z, S, p)02. vol. i„ text-fig. 3U, p. 211. • |