396 DR. R. W. SHUFELDT ON 



tlius formed foramen is far from superficial " *. This is a very 

 interesting statement, and will be commented upon further on in 

 this Y)aper. 



Forbes, in describing the anatomy of £iziu7~a, makes the state- 

 ment that " The ambiens muscle is large, and peculiar in that its 

 tendon 'perforates the large-sized triangular patella, just as it does 

 in Phalacrocorax and the extinct Hesperornis " t. 



When referring to this sesamoid in the Cormorants, Coues says, 

 in the fifth edition of his ' Key ' (p. 961), that " There is a bulky, 

 free patella, coexistent with a short cnemial apophysis or rotular 

 process of tibia, but perfectly distinct therefrom, as in Grebes." 

 This somewhat ambiguous description is made clearer by an illus- 

 tration of the patella in ^^Phalacrocorax hic7~istattis" which he 

 borrowed from a previous paper of mine. Nothing is said with 

 regard to the ambiens or the " perforation "in the patella, so this 

 note is quite useless for present purposes. 



Fi'om my own various accounts of the patellae in Cormorants 

 I select the following as best suited to throw light upon the 

 facts I propose to here set forth. 



In my above-cited article on the patella3 in birds (Proc. XT.S. 

 Nat. Mus. 1884, p. 330, fig. 7) I remark : " In No. 41 of ' Science,' 

 I presented a lateral view of the leg-bones of a Cormorant (Phala- 

 crocorax), showing the form of the patella in these birds. The 

 same specimen is given here, only an anterior view is chosen 

 instead of the lateral one. 



" This form is a particularly interesting one, and I am not 

 aware of any bird at present that can show a similar condition of 

 the parts in question. 



" On the face of it, it almost looks as if a patella had developed 

 of a size equal to the rotular process, and subsequently the two 

 became thoroughly united, and formed one large patella, articu- 

 lating as shown in the drawings I have made of it. I do not say 

 that this is actually the case, nor were the young of this spe- 

 cimen, which also belong to the collections at the Smithsonian 

 Institution, of a proper age to determine exactly the manner in 

 which this great bulky patella was developed." 



Apart from the suspicion expressed in this last paragraph, 

 which will be put into more exact terms further on, there are but 

 two opinions extant, at present, in regard to the development of 

 the patella in the Phalacrocoracidfe. They are the opinions of 

 Cairod and of Forbes, and have been set forth in their own words 

 above. 



There is but one consti-uction that can be placed upon Forbes's 

 view of a Cormorant's patella, a,nd tha,t view cannot be success- 

 fully defended. It will be noted above that, in his calling 



* Garrod, A. H. "Notes on the Anatomy of FlnUis atiJiinaa" P. Z. S. 1876, 

 p. 340, pi. xxviii. figs. 5, 6. The figures give the patella, indicating the position of 

 the foramen. 



t Forbes, Wm. Alex. " Note on some points in the Anatomy of an Australian 

 Duck {Bizhira lohata)," P. Z. S. 1882, p. 457. 



I regret to say that I have never had the opportunity of examining the patella in 

 this duck, and I doubt if \vc have a skeleton of it in the United States. 



