THE DEVELOPMENT OF SCAPHITES 639 



is well known from many parts of Europe and also India. Logan 1 

 thinks that all known Scaphites originated from one species in the 

 Gault of Europe, the Gault being transitional from the Lower to the 

 Upper Cretaceous, and have migrated from Europe to India and to 

 America. At that time he thought Scaphites monophyletic, but the 

 recent discovery by Mr. Anderson in the Upper Cretaceous of Oregon 

 and California of some new scaphite forms with different ontogeny, 

 and mingled with an entirely different fauna, makes it highly improb- 

 able that this is so. 



According to Anderson, 2 there was probably a communica- 

 tion established between the Interior Sea of America and the 

 Pacific province in Upper Cretaceous time, but none up to that 

 time, unless we go back of the Jurassic. However, J. P. Smith 3 

 has shown that there was a connection between the Indian prov- 

 ince and the west coast of America. An examination of the plates 

 in the volume on the Cretaceous fauna of India reveals a striking; 

 similarity between the Indian Scaphites and those in the Pacific 

 province. 



On the other hand, the fauna of the western Interior Sea is known 

 to be very similar to, if not identical with, faunas in just the other 

 direction. The writer has seen some Scaphites from the Upper 

 Cretaceous of New Jersey in Professor Stuart Weller's collection 

 which appeared to be of the same type as those coming from Montana. 

 Much the same fauna has been described from Texas and Alabama. 

 This seems to make it quite conclusive that migration took place 

 along the Cretaceous coast line from the eastern border around by 

 the Mississippi embayment up into the interior. Having got as far 

 as the Atlantic coast, we can explain the migration from western 

 Europe in much the same way as the migration from the Indian 

 province to western America. 



As the writer will attempt to show, the ontogenetic study of the 

 forms from the two regions, west coast and interior, simply corrobo- 

 rate these conclusions. 



' Field Col. Mus. Pub. 36, Geol. Ser., Vol. 1, No. 6. 



2 Anderson, loc. cit., p. 67. 



3 J. P. Sjnith, "Periodic Migrations between the Asiatic and the American 

 Coasts," American Journal of Science, Vol. XVII. 



