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University of California Puhlicatians in Geology [Vol.12 



Twitcliell, but S. norrisi may be easily distinguished by its much 

 larger size, relatively more depressed test, inframarginal periproct, 

 usually deeper posterior ambulacral marginal notches which, in some 

 specimens, are of nearly the same relative size, petals wider open at 

 their extremities, and by the fact that the rows of pores converge more 

 at the ends of the petals. It is most closely allied to 8. vaquerosensis 

 Kew, but differs in having deeper marginal notches and in that the 

 petals are wider open at their extremities. 



Geologic horizon. — Vaqueros formation. Lower Miocene, associated 

 with the fauna of the Turritella ineziana zone. 



Localities. — Holotype from "Eastern Monterey County, tive miles 

 northwest of Stone Canyon Coal Mine" (Pack) ; lectotype from ". . . 

 near mouth of the Alizo Canyon in the southern end of the San 

 Joaquin Hills, south of Santa Ana, Orange County, California" 

 (Pack), Univ. Calif, loc. 1157; at La Panza, on the San Juan River, 

 and in the mountains between the San Juan River and the Carrizo 

 Plains, San Luis Obispo County, California ; Santa Ana Mountains, 

 Orange County, California. 



SCUTELLA TEJONENSIS Kew, n. sp. 

 Plate 12, figures 2a, 26 



Holotype.— ^0. 11365 Univ. Calif. Coll. Invert. Pal. 



Size small. Measurements of holotype: anteroposterior diameter 

 26.0 mm., transverse diameter 25.6 mm., greatest height 4.6 mm. Out- 

 line of test subcireular, and with broad angular notches in the ambitus 

 in the posterior ambulacral areas; also a distinct notch in the odd 

 interambulaeral area ; margin rounded. Posterior portion of the sur- 

 face of the test more depressed than the anterior part. Apical system 

 decidedly eccentric to the anterior, with the summit of the test slightly 

 in front of the latter. Petaliferous portions of the ambulacral areas 

 extend almost to the edge of the test; each poriferous area equal in 

 width to about one-half the interporiferous area. Both outer and 

 inner rows of pores diverge continuously ; the inner rows to a greater 

 degree near their distal ends, where they come close to the outer rows ; 

 odd anterior petal broader than the others and somewhat elevated. 

 This form of petal contrasts markedly with the petals of other Cali- 

 fornia echinoids, the latter always possessing more or less convergent 

 rows of pores. Inferior surface slightly concave. Peristome round 



