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University of California Puhlications in Geology [Vol. 12 



infraraarginal. Mouth central. Broad, deep, straight ambulacral 

 furrows extend from the mouth to the edge of the test. 



Related forms. — This form closely resembles Astroelapsis ivhitneyi 

 Remond, but differs in its larger size, more elongate outline, more 

 elevated petals, more deeply sunken apical system, and in that the 

 petals are of the same width, whereas in the latter species the odd 

 anterior one is broader than the others. It differs from A. major 

 (Kew) and A. arnoldi (Pack) in that it lacks the interambulacral 

 and ambulacral depressions on the upper surface. 



Geologic horizon. — Lower Etchegoin (Jacalitos) formation, Lower 

 Pliocene. Associated with Dendraster gibbsii Remond and Astrodapsi-s 

 arnoldi peltoides (Anderson and Martin). 



Localities. — Holotype from "south of Garza Creek, a mile south 

 of Clark's place," Coalinga district, California; specimen no. 11037 

 fi'om same district, LTniv. Calif, loc. 2688. , 



ASTEODAPSIS MAJOE (Kew), n. sp. 



Plate 15, figures la, 16, Ic 



Astrodapsis tumidus Kew {large form). Univ. Calif. Publ. Bull. Dept. 

 Geol., vol. 8, 1915, p. 370, pi. 40, fig. 2. 



Cotypes.—^os. 11003 and 11337 Univ. Calif. Coll. Invert. Pal. 



Test large. Average measurements : anteroposterior diameter 53.9 

 mm., transverse diameter 46.9 mm., greatest thickness 15.1 mm. Out- 

 line subcircular, or suboval to subpentagonal. Margin considerably 

 thickened and notched in the ambulacra, the notching being deeper in 

 the two posterior areas. Upper surface greatly depressed, with the 

 apex usually coinciding with the apical system or immediately anterior 

 to it on the odd petal. Apical system is central. Interambulacral 

 areas are deeply and broadly grooved, and extend from the apical sys- 

 tem to the margin. A tendency toward faint grooving is present in 

 the ambulacral areas along the sides of the petals. Petals sj^mmetrical, 

 markedly elevated, broad, and extending to the margin. Inner rows 

 of rounded j^ores diverge until about one-half the distance to the edge 

 of the test, and then either converge slightly or parallel each other 

 to the end ; outer rows of elongate pores diverge at first to a greater 

 degree and when about one-third the distance to the margin converge, 

 becoming, near the end of the petal, rounded and close to the inner 

 rows ; both rows of pores reach the margin of the test. Each porif- 

 erous area at its widest part is equal to about one-third the width of 



