608 BULLETIN" 103, UNITED STATES NATIONAL MUSEUM. 



other places, but such connections seemingly were restricted, not of 

 wide extent as in upper Eocene and Oligocene time. 



As no upper Miocene has yet been identified in the West Indies 

 this is supposed to have been a period of high uplift which terminated 

 the connection between the Atlantic and Pacific oceans. The mid- 

 dle and upper Oligocene and lower Miocene sediments of Mexico, 

 Panama, Cuba, Haiti, Jamaica, Porto Rico, Anguilla, and Antigua, 

 although deformed by tilting and faulting are not intensely folded, 

 as are the older sediments. According to Hill, "in mid-Tertiary 

 time granitoid intrusions were pushed upward into the sediments of 

 the Great Antilles, the Caribbean, Costa Rican, and Panamic regions." 

 The information I obtained in Antigua and St. Bartholomew accords 

 with this opinion. 



That there was at some place interoceanic connection subsequent 

 to lower Miocene (Burdigalian) time is suggested, if not actually 

 proven, by the presence on Carrizo Creek, Imperial County, California, 

 of a coral fauna of post-Miocene Atlantic affinities. 1 



Roy S. Dickerson 2 in the paper cited below says regarding my 

 conclusion that the coral fauna of Carrizo Creek is of probably Pliocene 

 age: "His [Vaughan's] conclusions concerning the Pliocene age of 

 these beds rests upon the infirm basis of comparison with a Pliocene 

 coral fauna of Florida," and "All the coral genera except one occur 

 in the Bowden or associated horizons." The last statement is correct 

 in the restricted sense in which I use Bowden and its related zones, 

 and the first is correct in that I compared the fauna from Carrizo 

 Creek with that from the Pliocene Caloosahatchee marl of Florida; 

 but Doctor Dickerson evidently did not comprehend the entire basis 

 for my opinion. The following eight genera, now extinct in the 

 Atlantic Ocean but present in the Pacific, occur in the Bowden marl 

 and related zones, that is in Miss Maury's Santo Domingan section 

 and the La Cruz marl of Cuba, but are not known from Carrizo 

 Creek or from the Caloosahatchee marl: 



Placocyathus . Antillia. 



Placotrochus . Syzygophyllia. 



Stylophora. Pavona. 3 



Pocillopora. Goniopora. 



Neither the coral fauna of Carrizo Creek nor that of the Caloosa- 

 hatchee marl, as at present known, contains any of the coral genera 

 distinctive of the Bowden and related zones. These distinctive 



1 Vaughan, T. W., The reef-coral fauna of Carrizo Creek, Imperial County, California, etc., U. S. Geol. 

 Survey Prof. Paper 98, pp. 355-386, pis. 92-102, 1917. 



2 Ancient Panama Canals, California Acad. Sci. Proc, vol. 7, pp. 197-205, 1917 (date printed with title 

 July 30, 1917, received by me on Oct. 16, 1917). 



* Added from Miss Maury's Santo Domingan collections. 



