( 78 ) 

 DOWN TRACTS IN NESTLING BIRDS. 



COLLINGWOOD INGRAM. 



On p. *xiv. of the Practical Handbook of British Birds drngrscms 

 are given of the dorsal and ventral aspects of an altricial bird 





r^tUd. 





rapiTa.1 JroLcl' 



Suprrorhi/kl 

 1-racl- 



yhxrcli 





h1t}-» carpal 



T'Aa.cf' 



Zd-nar h-ctcl' 





CARRION-CROW {CoYVUS C. COrom) 3 DAYS OLD. 



for the purpose of subsequent reference to the pterylosis of 

 the pre-pennae down found in nestlings. 



The position of the so-called " inner supra-orbital tract " 

 in the diagram of the upper parts is certainly not typical for 



