235 



The syrinx is highly characteristic in the Caprimulgi. 

 Like the nearly related (?) cuckoos, we have both the 

 tracheo-bronchial and the purely bronchial syrinx. In- 

 deed, the stages are almost identical in the two groups. 

 Guculus and Caprimulgus correspond with a tracheo-bronchial 

 syrinx ; then we have Centropus and Podargus, and finally 

 the culmination in Grotophaga and 

 Steatornis of a syrinx furnished with 

 a membrana tympaniformis, which 

 does not commence until many rings 

 below the bifurcation of the tube, 

 the intrinsic muscles being attached 

 to the fijst ring which borders upon 

 it. It will be necessary to describe 

 the various syringes in some detail ; 

 . they have been studied and figured 

 by myself. ' In Nyctidromus alhicol- 

 lis, which will serve as a type of the 

 tracheo-bronchial ayriitx which ex- 

 ists in the Caprimiilgidae (s.s.), the 

 last four tracheal rings are closely 

 applied in contradistinction to the preceding, which are 

 separated by copious membranous intervals. The last two 

 tracheal and the first five bronchial semi-rings are ossified. 

 To the first of the latter are attached the intrinsic muscles. 

 In Batrachostomus we have the intermediate type of syrinx, 

 which may, however, be called bronchial. The first six 

 bronchial semi-rings and the last three tracheal are ossified, 



' ' On the Syrinx and other Points in the Anatomy of the Caprimulgidse,' 

 P. Z. S. 1886, p. 147. 



Fig. 113. — Sykinx of Nycti- 

 dromus albicolhs (after 

 Beddaed). 



