NOTES ON FOSSIL BIRDS— LUCAS. 547 



pressed, and at first sig-ht there appeared to be no surface for articu- 

 lation with the facet just mentioned. Close inspecti()n, however, 

 showed on the left side an apparent articular face of the proper size 

 to receive the fiat, articular portion of the pteryg'oid. thouo-h not pro- 

 jecting above the general level of the sphenoid. The basisphenoid of 

 Hesperornis has thus absolutely nothing of the ci-uciform shape, due 

 to the large, projecting l)asipter3^goid processes, so eminently charac- 

 teristic of the DromajognathaB. 



Among the Dinornithida?. Emeus, and Meionornis have compara- 

 tively short basipterj'goids. but even in these birds the processes 

 project markedly above the level of the basisphenoid, while in Hes- 

 perornis this bone was in appearance not unlike the corresponding 

 region of a loon, or penguin. The third articulation on the pterygoid 

 would be for the palatine, but it is not easy to imagine the shape of a 

 palatine that would fit such a surface and accord with the rest of the 

 bones. The bone considered as a palatine bv Professor Mai-sh is long 

 and slender, with an articulation indicated on one side at about one- 

 third the length of the bone; a somewhat similar, though imperfect, 

 bone is present in the specimen of Hes- 

 -perornis regalis belonging to the United 

 States National Museum, but neither of 

 these seems adjustable to the present 

 pterygoid. In the present instance the 

 pter3"goid la}^ immediatel}' over the left 

 quadrate, but in spite of this intimate fig. 3.-supposed lachkymal of ne^e- 



... iiiiij- rornis regalis. Slightly reduced. 



association, it appears probable that it 



is from the right side. With its point directed Ijackward the supposed 

 palatine articulation would be brought on the anterior side and in the 

 proper position for union with the palatine and vomer. Such a dis- 

 position would give an arrangement of the ])ones of the palate some- 

 what analogous to that found in the Cassowary. The bone heretofore 

 supposed to be a palatine ma}', perhaps, be the Aomer, although it is 

 difficult to account for the long portion back of the articulation. 

 The vomer is said to have been double, and judging by the freedom 

 of most of the bones of the cranium this may Avell have been the case. 

 The bone figured as vomer in Odontornithes appears rather small for 

 that of so large a bird as Hesperornh regalis. In the specimen of 

 He8])erornis gracilis under consideration no bone* representing the 

 vomer can be made out, nor are there an}- evidences of the presence 

 of maxillo-palatines. 



By one of the curious chances of fossilization, the fragile sphenoid 

 rostrum has been preserved. It is long and slender, and its anterior 

 portion underlies and unites with the mesethmoid precisely as it does 

 in Urinator. there being a further similarity between this genus and 

 Hesperornis in the large size of the interorlntal vacuity. This is very 



