S. W. Williston 305 



depressions were always the result of the compression to which the bones 

 were subjected. 



At present our knowledge of the skeleton of Nijctodadylus is nearly 

 complete, more complete perhaps than that of any ether pterodactyl 

 known. 



Its structure demonstrates the comparative unimportance of the scap- 

 ular articulation as a diagnostic or classificatory character. The struc- 

 ture of the skeleton throughout, even of the uotarium or consolidated 

 dorsal vertebrae, is very much like that of Oniithostoma save in the 

 scapula. From this it follows that the genus must be placed in the 

 same family with Ornitliostoma and OniWiocheirus. In my own opinion, 

 there is not even a subfamily difference. 



I still believe that the genus Pteranodon is identical with Ornitliostoma, 

 and that the former term must be abandoned. Plieninger (1. c), how- 

 ever, concludes that even if the two terms be synonymous, the name 

 Ornitliostoma has no claims for recognition, because it was not adequately 

 described or figured before Marsh described Pteranodon. Were this true, 

 and it may be, it would not be sufficient justification for the rejection 

 of Ornithostoma. Were the rule applied to Marsh's own names, a 

 large part of them would be rejected, as he rarely gave characters sub- 

 stantiating his terms. But there is a far w^eightier reason for the aban- 

 donment of the name Pteranodon. Prof. Seeley, according to his 

 statement,* pointed out to Prof. Marsh the toothless character of Or- 

 nitliostoma and showed him the evidence before Pteranodon was known! 



On every principle of nomenclature and justice the name Ornitliostoma 

 must take precedence over Pteranodon if these genera are found to be 

 identical, as I believe will be the case. 



Note. — Since the foregoing has been in type, the skull of the speci- 

 men described has been nearly wholly freed from the matrix. It has 

 no occipital crest, and the occiput is a little less produced than in the 

 figure; otherwise the outline is nearly correct. The fossil skull, thirty- 

 one centimeters in length, inclusive of the mandible, weighs less than 

 thirty-nine grammes! 



* Dragons of the Air. London, 1901. p. 182. 



