BIRD OR REPTILE WHICH f 725 



with double cup-shaped segments. Here was a dilemma ! The ichthy- 

 ornis had on what seemed reliable data been adjudged a bird ; but not 

 only was no bird ever known to have teeth set in sockets, but no bird 

 had ever yet differed so far from its fellows as to affect teeth at all, not to 

 mention the fact of its having resuscitated the fashion of a by-gone day 

 in having its spinal vertebrae cupped at both ends. When it lived, was 

 this creature, in which the types have become so strangely mixed, a 

 reptile, or after all a bird ? was a question that for a time made the 

 brows of the philosophers anxious even in the midst of their happiness 

 at the new discovery. They finally declared for the latter. There was, 

 therefore, no resource left but to extend the boundaries which had hith- 

 erto confined the avian territory, and institute a new sub-class for its 

 reception, whereat the ornithologists were greatly pleased and cordially 

 welcomed the toothbills among their feathered friends. 



Among the treasures which on December 7, 1872, Prof. Marsh and 

 his Yale College explorers brought back to New Haven, as the results 

 of their autumn reaping among the Rocky Mountains, was the nearly 

 entire skeleton, containing all the missing bones, of the royal hesper- 

 ornis and of another bi-concave vertebrated bird. 



The breastbone of the gigantic diver of the chalk is thin and weak, 

 and entirely without a keel ; in front it resembles the ostrich's or that 

 of the apteryx of New Zealand a group of birds presenting the great- 

 est range in time and also the widest geographical distribution over the 

 globe but in some respects it approaches to the penguin's also. The 

 wing-bones are diminutive, and the wings are rudimentary and useless 

 as organs of flight. The bones that girdle the thigh clearly exhibit a 

 resemblance to the corresponding bones of a cassowary ; yet, although 

 avian in type, they are peculiar and present some well-marked reptilian 

 proclivities. 



Furnished with these bones alone, and judging from his experience 

 of bird architecture, in plan hitherto undeviated from, no ornithologist 

 would have hesitated to relegate the remains to a place among the 

 birds ; and, had he been asked to restore the missing portions, he would 

 in all probability have devised some cross between the corresponding 

 parts of the divers, of the dabchicks (for their knee-cap resembles that 

 of the hesperornis), and of the ostrich-like birds, adding thereto a tail 

 somewhat after the model of the penguin's. Certain it is, however, he 

 would never have approached the features presented by the actual 

 bones. This primeval bird possessed a skull in its general form like 

 that of the great northern diver, but with a less pointed beak. The 

 jawbones, however, though they were originally covered with a horny 

 bill as in ordinary birds, are widely different. They are massive and 

 have throughout their length a deep groove which was thickly set with 

 sharp-pointed teeth evidence of carnivorous habits their crowns cov- 

 ered with enamel and supported on stout fangs. In form of crown and 

 base they most resemble the teeth of the reptiles found in the Maes- 



