DR, R. W. SHUFELDT's MORPHOLOGICAL 



he could procure, and it gave me great pleasure to forward it to 

 him along with a few others that I had collected, in response to 

 his request for such, material. 



The characters of that skeleton have escaped me, but the 

 reader can easily compare such forms as he may have at hand 

 with what follows. 



My former memoir (P. Z. S. 1885) contains an extensive 

 account of the osteology of Chordeiles aud PhalcBnoptilus ; so in 

 the present connection I may point out what has been already 

 ascertained in regard to a comparison of these Caprimulgine 

 forms and Geococcyx with the Trogons. Thanks to my friend 

 Mr. Sage I have before me a fine alcoholic specimen of our 

 American Whip-poor-will ; but I do not intend to dissect that 

 until we enter upon the next section of this memoir, wherein 

 it will constitute my type for the general anatomy of a Capri- 

 mulgine bird. 



A comparison of the skulls of Trogon, Chordeiles^ and Geo 

 coccyx need not detain us long, for they have but very few 

 characters in common. With respect to the skulls of Trogon 

 and Geococcyx they may be dismissed by stating that they differ 

 from each other in every essential particular, beyond the fact 

 that they are both skulls of birds. 



This difference is quite as great when we come to compare the 

 skulls of Chordeiles and Geococcyx^ for here, too, it would be 

 very difficult, if not quite impossible, to pick out a single feature 

 in the one that would in any way be comparable to the corre- 

 sponding one in the other. 



Excej^t for the fact, as stated, that they are both skulls of birds, 

 they are totally unlike. 



Not nearly so much so is this the case with Trogon and 

 Chordeiles ; for, different as the skulls of these two forms really 

 are, I think I can see a certain resemblance between them, 

 slight as it is. 



Still even here, at the best, it is little more than a superficial 

 likeness; they have, however, in common the basipterygoidal 

 processes, if nothing beyond that. Their mandibles, as we know, 

 are entirely dissimilar. Notwithstanding this, it would be far 

 easier for us to conceive that a Trogon's skull was a very much 

 modified Caprimulgine one than it would be to picture any 

 relation between it and the skull of Geococcyx. 



With these facts before us we are not surprised to find, what 



