OCR Text |
Show 1903.] SYRINX OF T H E ACCIPITRES. 161 are attached to the middle of the second bronchial semirmg. Ihe first three bronchial rings are closely laid by each other and the tracheal rings; larger interspaces separate the ensuing bronchial semirings ; but there is no wide membrana tympaniformis externa. Genus MILVUS. In this genus, at least in the species M. ictinus, the bronchidesmus is incomplete. There is no conspicuous membrana tympaniformis externa. The intrinsic muscles are attached to the second of the entirely free semirings, i. e. those which are not fused with the pessulus. The syrinx therefore is constituted on the plan of that of Nisaetus. Genus DRYOTRIORCHIS. D. spectabilis is a Hawk with an altogether unusual form of windpipe (text-fig. 18): that is to say, unusual as to details, for it distinctly belongs to the Aquiline as opposed to the Falconine division Text-fig. 18 Syrinx of Dryotriorchis spectabilis. X 3. of the group. In this genus the bronchial character of the syrinx, suggested among the Aquiline forms, is more strongly emphasised thaS in any other Accipitrine genus which I have had the opportunity of examining. In fact this Hawk may be fairly described as possessing a bronchial syrinx. This syrinx is, however an exaggeration of the conditions occurring in such a form as Nisaetus In that genus and its allies four or five rings, which P R O C ZOOL. Soc-1903, V O L . II. No. XI. 11 |