TIIIKD ANNUAL MEETING -•) 



The chalks of Kansas have j'ielded several of this species, the best 

 specimens being- at Yale, and in Professor Williston's collection at the 

 I niversitj^ of Kansas. It is scarcely necessary to describe to orni- 

 thologists a fossil bird so Avell known as the Hesperornis. This giant 

 diver stood five to six feet high, wingless, but emiJowered by adapta- 

 tion and by special modification for feats in diving and swimming. 

 Lucas calls attention to the fact that its feet acted sideways instead 

 of forward and back under the body after the manner of swimming- 

 Tsirds. 



Its jaws were set with numerous small, conical teeth, which were but 

 mosasaur teeth in miniature, arranged in continuous grooves. In 

 the upper jaw the teeth were confined to the maxillae, the pre-maxillae 

 being edentulous. Both mandible and jaw were covered with a horny 

 beak, unlike its Jurassic predecessor, the Archaeopteryx. In general 

 appearance it resembled the loon or great northern diver save it was 

 destitute of wings. It was a magnificent diver and swimmer and the 

 largest of its kind. Long use had developed its feet while continued 

 disuse had reduced its wings to rtidiments consisting of one vestigial 

 bone. Though plainly descended from birds originally empowered with 

 flight, the dwarfed humerus is all that is left in proof. Yet, on the 

 ■distal extremity, are facets for articulation with the radius and ulna, 

 ■which evidence their former existence and the existence of the whole 

 wing organ, it being presumed that the flightless birds are derived from 

 those with wings. The bones of Hesperornis are remarkably hollow, 

 unlike some swimming-birds whose bones incline to be solid, for the 

 reason that nearly half of their weight is sustained by water. Its body 

 was covered with feathers like those of Apteryx, as shown by Professor 

 "Williston, who has found specimens exhibiting the impression of skin 

 and feathers. 



The caudal vertebrae shoAv that the tail of Hesperornis differed from 

 that of modern birds. It was not so long and reptile-like as that of 

 Archaeopteryx but more so than that of modern birds. So in the inter- 

 esting drawing by Gleason, made under the direction of Lucas, in his 

 book entitled Animals of the Past, there is shown a sort of intermediate 

 stage between Archaeopteryx and modern forms, as will appear in the 

 accompanying cut. 



Here again we have a blending of the reptilian and avian characters 

 with a prex^onderance of the latter. In habit it was carnivorous as 

 evidenced by its teeth, and flsh doubtless constituted its diet. The 

 other known Cretaceous birds differ little from modern ones. Between 

 Cretaceous and Eocene times they had lost their teeth and certain other 

 ancestral peculiarities to such an extent that the birds of Tertiary 

 iime are like those of the present day. The ornithologist must now 

 reckon with a toothed as well as a toothless division in both orders, 

 TJatitae and Carinatae. In the Ratitae, to which Hesperornis belongs, 

 we find all the remaining rejiresentatives of the order toothless, and 



