14 



Chione f e xnamio en s i s , new sp. 

 PI. 1, fig. 4 and 5. 



Shell small, sub- triangular, thick; lunule large, 



?, of apiie &r upp ind 



cordate, distinct, bounded by an impressed line; anterior 

 dorsal slope short, posterior dorsal slipe long and only 

 very slightly convex; escutcheon broad arid flat or slightly 

 concave; ligamental channel equal in length to one third 

 of posterior dorsal slope; base roundly arcuate; shell marked 

 by concentric lamellae which become more prominent upon 

 erosion of specimen, when they give it a corrugated appear- 

 ance; radially marked by numerous fine ribs. 



This species is common from the lower part of the 

 Fernando formation. It was probably included under Chione 

 jiuccin_ct_a by Gabb, who lists the latter from the Fernando 

 Pliocene. This species differs from other chiones by its 

 small size, large broad lunule, lamellar structure, and broad 

 escutcheon. 



Altitude 18 mm.; length 22mm.; thickness 10.5 mm.; 



lunule length 6 mm., width 4 mm. 



v* heinfi l?'.i and i?6 sat. re- 



