GEOLOGICAL EBLATIONS OF BIEDS. 237 



and its remainp show a bony tail as long as the body, consisting 

 o£ twenty separate vertebree with feathers implanted on either 

 side (a pair to each vertebra), for its whole length, and radiating 

 from its tip. It had a strongly curved " furcula " or merry- 

 thought, and a keeled sternum. Its foot was completely like that 

 of an ordinary bird, but in the pinion there were two distinct 

 metacarpal bones and two curved claws. The wing was pro- 

 vided with long " remiges." 



Eemains of a Bird, the jaws of which bore true teeth, have 

 been found in Sheppey*. It has been named Odontopteryx 

 toliapus. 



Two very remarkable fossil Birds have been discovered in 

 the Cretaceous rocks of North America. One of these, called 

 Ichthyornis, differed from all existing Birds in having the centra 

 of its vertebrae concave both in front and behind. It had also 

 true teeth lodged in distinct sockets. Its wings were well 

 developed ; its metacarpals anchylosed together, and its sternum 

 keeled. The other form, called Hesperornis, had true teeth, 

 lodged, not in distinct sockets, but in continuous grooves in the 

 jaws. The centra of its vertebrse were saddle-shaped, as in 

 ordinary birds, but its sternum had no keel. Its most extra- 

 ordinary character, however, was its extremely defective wings, 

 in which the skeleton of not only the pinion but of the fore-arm 

 appears to have been absent, while the humerus itself, though 

 long, was extremely slender. 



Some twenty other kinds of Cretaceous Birds have been 

 described, most of them of wading, more or less aquatic kinds. 

 Amongst these are Palceotringa and Telmatobius — allied to the 

 Sandpipers and Rails. 



When we advance to the Tertiary epoch, a number of Bird- 

 remains make their appearance. 



Amongst those found in the Eocene rocks in Europe are 

 Alethornis and Protornis, the latter resembling a Lark, and 

 Palcegithalus, reminding us of a Nuthatch ; also Cryptornis and 

 Haleyomis, which were like Kingfishers. The last-named fossil 

 was found in the Isle of Sheppey, where also Liihomis was 

 found, which seems to have been allied to the modern American 

 Vultures of the genus Oathartes. A gigantic Wading-bird, called 

 Gastornis, of the size of an Ostrich, has left its remains in Erance. 

 An Eocene Woodpecker, Uintomis, has been found in America. 



* See^Quart. Journ. Geol. Soo. xxix. p. 511. 



