154 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Sek. 



ten keepi Arn., P eaten lecontei Arn., Pecten veatchi Gabb, 

 Pinna species, Cassis species, Conus (giant), Cyprcsa species, 

 Dolium (Malea) cf. ringens Swain., Oliva cf. porphyria L., 

 Solarium species, Stromhus cf. granulatus Gray, Turritella 

 (giant), Cit/am species, C/j'/'^a^^^r howersi Wea-ver, Clypeaster 

 carrizoensis Kew, Clypeaster deserti KJew, Encope tenuis Kew, 

 Mceandra bowersi Vaughan, Dichocoonia merriami Vaughan, 

 Plesiastrcea californica Vaughan, Siderastrcea californica 

 Vaughan, Siderastrcea mendenhalli Vaughan, Solenastrcea fair- 

 banksi Vaughan, Porites carrisensis Vaughan. 



This is a thoroughly tropical fauna, all the species being 

 nearly related to members of the Gulf or Panama fauna, with 

 the exception of the Astrseidae, which indicate still warmer 

 water than that of Panama. The Astrseidse are most nearly re- 

 lated to Caribbean forms, and suggest the possibility of a late 

 Miocene connection between the Atlantic and the Pacific. There 

 is nothing else in the fauna, however, to make this probable, 

 T. W. Vaughan*, who has described the coral fauna of the 

 Carrizo, leaves the question in abeyance. Further study by 

 R. E. Dickerson has cast doubt upon the Pliocene age of the 

 Carrizo fauna, and it may yet be placed in the Miocene, to 

 which Arnold first assigned it. 



It is clear that the real tropical belt extended up to Imperial 

 County, California, lat. 33° N., the head of the ancient Gulf of 

 California. The corals have not been found in the Carrizo 

 formation on Cerros Island; it is probable that then, as now, 

 the ocean side of Lower California was cooler than the Gulf in 

 the same latitudes. The Carrizo beds of the Gulf were de- 

 posited in water that was probably considerably warmer than 

 68° F. min. temperature. 



Climatic Distribution of Faunas in Fernando-Purisima 

 Epoch of the Lower Pliocene. 



I. Oregonian (Eel River, California, to Puget Sound, lat, 

 40°-49° N. ) . Cardium gra^nlandicum, Chione securis, Area tri- 

 lineata, Cardium meekanum, Pecten dilleri, Pecten caiirinus, 

 Spisula albaria, Spisula voyi, Saxidomus giganteiis, Thyasira 

 bisecta, Dendraster oregonensisC\dir\<i. The present temperature 



* The reef-coral fauna of Carrizo Creek, etc, U. S. Geol. Survey, Prof. Paper 

 No. 98-T, pp. 353-395, 1917. 



