Fossil Birds in the Marsh Collection of Yale University 17 



Graculavus velox Marsh. 



{Plate VI, Figs. 33; Plate VII, Fig. 49.) 



Marsh, Amer. Journ. Sci., ser. 3, III, 1872, 363. 



Holotype. Cat. No. 855, Peabody Museum, Yale University. Hornerstown, 

 New Jersey. Cretaceous. J. G. Meirs, collector. 



This species is based upon a fossil fragment of the proximal end of 

 a left humerus (not the proximal "half" as Marsh has it). It is 

 chipped and otherwise imperfect, the color being a muddy, darkish 

 green. Professor Marsh said of it that "In its general features this 

 humerus [sic] resembles that of the common Cormorant {Graculavus 

 carho Linn.), although indicating a somewhat smaller species." 

 (p. 363.) 



As it was upon this fragment that the genus Graculavus was based, 

 I have most carefully compared this type material with the proximal 

 ends of the left humeri of a number of species of Cormorants, and in 

 Plate VII, Figures 48-55, I illustrate these comparisons, not only with 

 Phalacrocorax but with other birds. 



It may be seen at a glance that the proximal end (anconal aspect) 

 of the humerus of Marsh's Graculavus in hardly any particular 

 agrees with the corresponding characters as they are found in the 

 Phalacrocoracida\ 



In the first place, the radial crest of the humerus in a Cormorant 

 has the appearance of having been shaved off, or in other words, it is 

 long and unusually low. In Graculavus the radial crest is chipped off, 

 but the indications are that it was rather tall and short as in an 

 Oyster-catcher {Hmnatopus) (Fig. 50). 



On the ulnar aspect of the head of the humerus in the Phalacrocor- 

 acidx, the surface between the radial crest and the ulnar area 

 over the pneumatic fossa, is well defined and markedly excavated; 

 while in Graculavus it is relatively broader, very shallow, and not 

 especially defined. This is as we find it in some other birds — strik- 

 ingly so in such species as Orthorhampus magnirostris. This is not 

 seen in Figure 51 for the reason that the anconal and not the palmar 

 aspect of the bone is viewed there. 



Again, comparing the anconal aspect of the head of the humerus of 

 Graculavus velox with that of a Cormorant (P. carbo, P. urile), we find 

 that the characters differ entirely. 



1. On the radial side of the bone in Graculavus, distad to the caput 

 humeri, there is a wxll-defined and somewhat circumscribed depres- 

 sion. This area is perfectly flat in Phalacrocorax. 



