434 University of California Publications in Geology [Vol. 8 



Etehegoin. In a subsequent paper 38 he divided the Upper Miocene 

 into two faunal zones, the lower or San Pablo-Santa Margarita zone, 

 and the upper, or Etehegoin zone. 



In 1914 Mr. W. A. English 39 published a paper on "The Fernando 

 Group near Newhall, California," in which a list of 79 marine inver- 

 tebrate species is given ; these were obtained from the beds at the base 

 of the Fernando, which had been regarded as equivalent to the San 

 Pablo of middle California. The fauna listed by English is obviously 

 much younger than that of the San Pablo and belongs rather to the 

 Pliocene than to the Miocene. English 's conclusions are as follows : 



"The fauna listed by Arnold and Anderson from the Etehegoin 

 of Coalinga contains eighty-four determined species, of which eighteen 

 are common to the lower Fernando, ten of these being found in the 

 Purisima also. Most of the species common to the Fernando and the 

 Etehegoin have an extended vertical range, so that the relationship is 

 not so definitely shown as between the Fernando and the Purisima. 

 It is probable that the lower Fernando and the Etehegoin do not 

 differ greatly in age." 



Position op San Pablo in the Neocene Section of California 

 Relation to Etehegoin and other Formations correlated with the 

 San Pablo. — The fauna of the San Pablo is distinctly older than that 

 of the Etehegoin and certain other local California formations with 

 which the latter has been correlated, including the Purisima, Merced, 

 Fernando, Wildcat and the Pliocene deposits at San Diego and San 

 Pedro. A comparison of the fauna of the Etehegoin. as listed by 

 Arnold (Bull. 306. U. S. G. S., pp. 30-36), with that of the San Pablo 

 shows some striking differences. The number of species common to 

 the two is 38, or 25+ per cent, of the determinable species in the San 

 Pablo; of these nearly all are either Recent or have a long range 

 and are not generally recognized as good horizon determiners. For 

 example, none of the Pecten species and none of the echinoderms of 

 the San Pablo are found in the Etehegoin or in the other formations 

 with which the latter is correlated. Again, the Etehegoin contains a 

 larger percentage of Recent species. Arnold states the percentage of 

 Recent forms in the Etehegoin to be 35. Later collecting in the Etehe- 

 goin has increased this percentage to over 40. The percentage of 



38 ' ' Geologic Bange of Miocene Invertebrate Fossils of California, ' ' Calif. 

 Acad. Sci., 4th series, vol. Ill, p. 161, 1912. 



so Univ. Calif. Publ. Bull. Dept. Geol., vol. 8, no. 8, pp. 203-218, 1914. 



