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University of California Publications in Geology [Vol. 9 



surface of whorls has four spiral ribs, of which the posterior is much 

 more prominent, this giving the top a tabulate aspect which is not 

 due to impression at suture; at the base are a number of slightly 

 nodose, spiral ribs of which the two inner are the most prominent. 

 Suture slightly impressed, between two strong revolving ridges. All 

 the major ribs and intercalaries are nodose. 



Height, 16.2 mm. ; maximum diameter, 16.7 mm. 



This species resembles rather closely Calliostoma coalingensis 

 Arnold, also found in this district. In Calliostoma etchegoinensis, 

 n. sp., however, all the ribs have well-developed nodes, and the tabulate 

 upper surface of whorls is not at the suture but extends from a strong 

 ridge immediately below suture to the upper ridge on sides of whorls. 



PURPURA TURRIS, n. sp. 

 Plate 7, figure 4 



Type in collections of University of California Department of Palaeontology, 

 from locality 2110. 



Shell thick, medium in size, spire and canal short, turreted ; whorls 

 about six, shouldered, channeled immediately below suture ; mouth 

 subovate, outer lip much thickened; canal open, inclined slightly to 

 the left ; body-whorl ornamented by about seven revolving ribs, of 

 which four are more prominent, of the ten longitudinal varices on 

 body-whorl of type two are heavier and lamellar. 



Height, 40 mm. ; maximum diameter, 28.5 mm. 



Occurrence in the lower Etchegoin formation, west of Coalinga, at 

 University of California locality 2110. 



NATICA (NEVERITA) CONVEXA, n. sp. 

 Plate 7, figures 1, 2 

 Type from University of California locality 2091. 



Shell slightly ovate with elevated spire ; whorls about four, strongly 

 convex, becoming somewhat flattened near the top, giving the whorls a 

 slightly tabulate appearance; near the mouth the lower part of body- 

 whorl curves downward considerably ; surface covered by numerous 

 oblique incremental lines ; suture distinct, not appressed ; umbilical 



