CUCULI 



L'77 



being perfectly complete rings, the trachea dividing, ' as in the 

 mammalia.' Prom the seventh onward all the bronchial rings 

 are semi-rings, the intrinsic muscles being attached to the 

 tenth. This is one extreme of the series, the other being 

 offered by such a type as Piaya. In Piaya (see fig. 137) 

 there is a purely tracheo-bronchial syrinx. The third bron- 

 chial semi-ring is of compara- 

 tively speaking enormous size, 

 and to it are attached the in- 

 trinsic muscles of the syrinx. In 

 Saurothera we have a syrinx 

 which is quite similar save for 

 the fact that the third bron- 

 chial ring is not enlarged. 

 Diplopterus is much the same 

 as the last. Guculus has also 

 a perfectly typical tracheo-bron- 

 chial syrinx. In Eudynamis 

 there is a cuculine syrinx, the 

 last tracheal and the first three 

 bronchial semi-rings being ossi- 

 fied ; the intrinsic muscles are 



attached, as in Piaya, to the fig. ui.-Syhx^xo^ Piaya cayancr 

 third bronchial semi-ring. (aftek Beddabd). 



Phoenicophaes is much the same, 



The remaining genera of cuckoos whose syrinx is known 

 are nearer akin to Crotophaga, though in them the bronchial 

 syrinx is not quite so typical. In Gentropus ateralbus, for 

 instance, the first fifteen rings of the bronchi are incomplete, 

 internally and are closed by membrane, but the membranous, 

 area is narrow ; this area widens out at the sixteenth ring,, 

 which with the following is much stronger than the pre- 

 ceeding and succeeding rings of the bronchus ; to the sixteenth 

 ring are attached the intrinsic muscles of the syrinx. Pyr- 

 rhocentor and Geococcyx have a similar syrinx. The syrinx of 

 Guira is in many respects very remarkable. On a superficial 

 view it is not unlike that of Guculus. The voice organ in 

 this genus is placed further forwards than in the genera just. 



