EXPLANATION OF PLATE 15 



Fig. 1. — Scutella norrisi Pack. View of abactinal surface. Natural size. 



Diameter through anterior petal, about 75 mm. Occurrence, near the 

 mouth of the Alizo Canyon, in the southern end of the San Joaquin Hills, 

 south of Santa Ana, Orange County, California. University of California 

 locality 1157. 



Figs. 2a and 2b. — Scutaster andcrsoni Pack. Natural size. 



Fig. 2a. View of abactinal surface. Diameter through anterior petal, 

 53 mm. Occurrence, in the Mount Pinos Quadrangle, California, at the 

 southern end of the San Joaquin Valley, about three and three-quarters 

 miles northeast of Antimony Peak. 



Fig. 2b. Anteroposterior section. 



[304] 



