444 On the Shoultler-girdle in Cretaceous Ornithosauria. 



the carpus to have the same structure in the toothless 

 Ornithosaurs from Kansas, and discussed it fully in April 

 1882 (Am. Journ. Sci.), though without, mentioning memoirs 

 in which the structure had been figured, and from which the 

 interpretation appears to be taken. 



If, then, the resemblances in the bones which led Professor 

 Cope to refer the early discoveries of American Ornithosaurs 

 to Ornithocheirus have to be transferred to Ornithostoma, it 

 does not affect the organic identity of the type ; and it is 

 by means of the excellent contributions to knowledge made 

 by Professor Marsh that I am able to establish the conclusion 

 that the dentigerous and edentulous Ornithosaurs of the Cre- 

 taceous rocks of Europe and America belong to the same 

 subordinal group. I long ago pointed out (Ann. & Mag. Nat. 

 Hist., August 1870) how small is the classificational import- 

 ance to be attached to presence or absence of teeth in Ornitho- 

 saurs and in Birds; and while the discovery of lchthyornis 

 by Prof. Marsh demonstrated that generalization among birds, 

 the discovery of these Ornithosaurs, which mainly differ in 

 their teeth, while they agree in the typical parts of the skeleton, 

 gives it a parallel justification among the Ornithosauria. 

 Whether the name Pteranodontidas can be retained for a 

 family to include the genus Ornithostoma remains to be 

 established ; for it is not improbable that animals will be 

 found in which there is a partial development of teeth, and 

 that Ornithosauria will eventually parallel Cetacea in the 

 development and suppression of dentition. 



I have used the name Ornithocheiroidea for the order 

 (Journ. Linn. Soc. vol. xiii. p. 96), and that name may be 

 found convenient as indicative of characters of skull, shoulder- 

 girdle, carpus, vertebrae, and other bones in which the 

 Cretaceous modification of the group differs from the Ptero- 

 dactylia, which is chiefly characteristic of the Middle Secondary 

 rocks, though I believe not absolutely limited to them. 



Professor Zittel ('Handbuch der Palaeontologie') has referred 

 to my early proposal to name the fossil flying animals Saurornia 

 (Rep. Brit. Assoc, Bath, October 1864, Sections, p. 69, and 

 Ann. & Mag. Nat. Hist., February 1 865) . The new facts then 

 brought forward necessitated a new name for the subclass. 

 When 1 afterwards found that Prince C. L. Bonaparte, 

 adopting von Meyer's view that the group formed an order, 

 proposed to name the order Ornithosaurii in 1838, 1 adopted 

 the name Ornithosauria, though it seemed a less suitable 

 name, and was originally given to only one division of the 

 animals comprised in Saurornia. 



De Blainville had suggested Pterodaetylia and J. J. 



