1885.] 



MR. F. E. BEDDARD ON THE CUCKOOS. 



177 



accompanying; figure ; further down it is continuous witli the 

 humeral tract ; on the pectoral and abdominal regions the tract on 

 either side is very narrow, only two or three feathers wide upon the 

 hinder portion of the sternum, and terminating just in front of the 

 cloacal aperture ; the widest section of the pectoral portion of the 

 tract is close to the origin of the humerus, where it gives off a short 

 branch to the under surface of the wing; beyond this branch the tract 

 is about three feathers wide and narrows gradually, as already stated, 

 to its termination just in front of the cloaca. 



Fig. 5. 



Pterylosis of Piaya cayana. 



Just on a level with the posterior margin of the sternum (as near 

 as T could judge from a specimen that has been considerably 

 damaged) the breadth of the ventral tract decreases from three to 

 two feathers, and at this point the outer row of feathers diverges 

 somewhat from the inner tract and thus forms a small rudiment of 



Proc. Zool. Soc— 1885, No, XII. 12 



