18 R. W. Shufeldt 



2. The head of the bone in Graculavus, centrally, curls over a 

 strongly marked excavation, which is extended back behind the 

 ulnar projection. No such excavation occurs in Phalacrocorax. 



3. In Graculavus the pneumatic fossa is short, defined from the 

 mesial, elevated, longitudinal area of the shaft by a low, sharp crest, 

 there being an interval between the two. In Phalacrocorax the for- 

 mation is entirely dljferent: the pneumatic fossa is broad and long, 

 merging everywhere with the surface of the shaft, being as broad below 

 as it is above, and the aforesaid crest is absent. As a matter of fact, 

 Graculavus is in no way related to the Phalacrocoracidoe, and the type 

 humeral head or proximal end is that part of the humerus which 

 belonged to some apparently extinct species, which was not a stegan- 

 opodine one at all. 



As Professor Huxley long ago pointed out for us (P. Z. S., Apr. 11, 

 1867), such birds as Gulls, Plovers, Oyster-catchers, Curlews, and 

 their allies, by him grouped as the Schizognalhous birds, hold many 

 osteological characters in common. He worked them out principally 

 with respect to certain structures of the skull; while I may say here 

 that similar resemblances are found throughout the skeletons of such 

 genera, or the representatives of such genera, as I have just named. 



For example, if we critically compare the humerus of a Lanis with 

 that of any Plover {VancUus, Charadrius, etc.), and these again with 

 the humeri of Ihematopiis, Orthorhampus, Numenius, Philohela and 

 so on, we at once observe that a general set of characters are present 

 in the humeri of them all. In some a certain character may be strong 

 or pronounced, and in another it may be but feebly developed; while 

 the general fades of the humerus cannot be mistaken. Now Gracu- 

 lavus had the majority of these schizognathine characters pronounced, 

 in so far as the head of its humerus was concerned (see Figs. 50, 51 

 and 54); and so evident are these that, through an examination of 

 this fragment, a well-informed avian osteologist could almost with 

 certainty predict that Marsh's Graculavus was not only a schizog- 

 nathous bird, but that it possessed more or less well-marked "supra- 

 orbital glandular depressions," which Cormorants entirely lack, and 

 so on for other skeletal characters. 



Graculavus did not belong among the Alcida^; and it was, judging 

 from this fragment of its humerus, far less like any of the Longipennes 

 (Gulls and their allies) than it was a number of Limicolce. In other 

 words, it was a limicoline species, and most nearly related to the 

 Charadriidw and the HamiotopodidK, that is, the Plo\-ers and Oyster- 

 catchers. 



