EXPLANATION OF PLATE 28 



Figures approximately natural size. 



Fig. la. Dendraster coalingaensis Twitcliell. Specimen 11383, Univ. Calif. 

 Coll. Invert. Pal. Upper surface of test. Coalinga district, Fresno County, Calif., 

 Univ. Calif, loc. 2108. Upper Etchegoin formation, Middle Pliocene. 



Fig. Ih. Dendraster coalingaensis Twitchell. Same specimen. Lower surface 

 of test. 



Fig. Ic. ' Dendraster coalingaensis Twitchell. Same specimen. Lateral surface 

 of test. 



Fig. 2a. Dendraster arnoldi Twitchell. Specimen 11384, Univ. Calif. Coll. 

 Invert. Pal. Upper surface of test. Sargent Oil Field, Santa Cruz County, Calif., 

 Univ. Calif, loc. 3129. Upper Etchegoin formation. Middle Pliocene. 



Fig. 2h. Dendraster arnoldi Twitchell. Specimen 165701, U. S. Nat. Mus. 

 Lower surface of test. Zapato Creek, Coalinga district, Fresno County, Calif. 

 Upper Etchegoin formation. Middle Pliocene. 



Fig. 2c. Dendraster arnoldi Twitchell. Specimen 11384. Lateral surface of 

 test. 



Fig. 3a. Dendraster perrini (Weaver). Specimen 11018, Univ. Calif. Coll. 

 Invert. Pal. Upper surface of test. Coalinga district, Fresno County, Calif. 

 Upper Etchegoin formation, Middle Pliocene. 



Fig. Sh. Dendraster perrini (Weaver). Same specimen. Lower surface of 

 test. 



Fig. Se. Dendraster perrini (Weaver). Same specimen. Lateral surface of 

 test. 



[ 208 ] 



