280 Mr. H. G. Seeley on Oniithopsis, 



order of animals. One of the British-Museum fossils is from 

 Tilgate ; the other, probably from the Isle of Wight, is labelled 

 South-east of England. They are of size and structure and 

 texture such that both might well have belonged to the same 

 kind of organism ; and as no other remains are known to 

 which either bone approximates, they are here considered to 

 indicate the same animal. One vertebra is from the lower part 

 of the neck, and the other from the lower part of the back. 

 When perfect, the neck-vertebra can scarcely have measured 

 less, from the back to the front of the centrum, than ten inches. 

 The neck would appear to have been carried erect, after the man- 

 ner of birds. If seven cervical vertebrje were to be presumed 

 (and there can scarcely have been fewer) , it would give a neck 

 from four to five feet long, and an animal of a minimum heiglit 

 of from ten 'to twelve feet, while it is not impossible that it may 

 have been twice or three times as hi^-h. Both vertebrae asrree 

 in being constructed after the lightest and airiest plan, such as 

 is only seen in Pterodactyles and birds ; and they agree in 

 possessing pneumatic foramina, which are an avian and orni- 

 thosaurian peculiarity. The foramina are of enormous size, 

 and approximate to those of Pterodactyles rather than to those 

 of birds. Seeing that in living animals these foramina exist 

 for the prolongation of the peculiarly avian respiratory system 

 into the bones, and that no other function is known for them, 

 we are compelled to infer for this animal bird-like heart and 

 lungs and brain. Both in Pterodactyles and birds one type of 

 brain coexists with these foramina ; therefore there is no 

 reason to suspect a different organization for these specimens. 



Our animal is therefore clearly ornithic. But it docs not 

 conform closely in the shape of vertebra? to either Pterodactyles 

 or birds. And from the bones preserved, and many other in- 

 dications of allied animals which I have seen from the Wealden 

 and Potton Sands, I anticipate that it will form the t}^e of a 

 new order of animals which will bridge over something of the 

 interval between birds and Pterodactyles, and probably mani- 

 fest some affinity with the Dinosaurs. 



In view of these considerations it is impossible not to recall 

 with interest the gigantic ornithic footprints described by 

 Mr. Beccles and Mr. Tylor from the Wealden. They might 

 not improbably have been the tracks of this animal. 



The Mantellian specimen in the British Museum, numbered 

 28632, is apparently a late cervical vertebra, with the centrum 

 about nine inches from front to back, six inches from side to 

 side, and about seven inches from the base of the neural canal 

 to the base of the vertebra. It is much worn, the neural arch 



