1016J Nomland: Invertebrate Zones of Jacalitos and Etehegoin 87 



callus large, rather prominent, completely covering the umbilicus, no 

 groove present on its surface. 



Height of type, 17.8 mm. ; greatest diameter, 16.5 mm. 



Occurrence at University of California localities 2091, 2093, 2096, 

 in the Etehegoin formation northeast of Coalinga, California. 



This species is distinguishable from Natica recluziana Petit, which 

 is also found in this district, by the convexity of the whorls, the 

 tabulate appearance, and the downward curving of the body-whorl 

 near the mouth. 



Transmitted February 26, 1915. 



