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University of California Publications in Geology [Vol. 13 



Family Gastrochaenidae 

 Genus GASTROCHAENA Spengler 

 GASTEOCHAENA, sp. 

 Plate 31, figure 1 



Type specimen no. 12282, Coll. Invert. Palae., Univ. Calif., loc. 2179. 



Several specimens which appear to be the protective tubes of some member 

 of this genus were obtained at localities 2179 and 2151, Santa Ana Mountains, 

 California. One of these, specimen no. 12282, which is broken at both ends, 

 has a length of 62 mm. and a diameter of 5 mm., at the smaller end and about 

 9 mm. at the other. The shell is thick and roughened externally by irregular 

 constrictions. The largest specimen shows the bottom of the boring. The 

 lower end is abruptly but evenly rounded with a nearly circular cross-section. 

 This specimen has a diameter of 16 mm. at the bottom and 14 mm. at a point 

 30 mm, higher. 



These specimens resemble the figures by Stolzisky of G. aspergil- 

 loides Forbes. 



Horizon. — Chico group, zonal position uncertain. 



Class GASTROPODA 

 Family Pyramidellidae 

 Genus ODOSTOMIA Fleming 

 ODOSTOMIA SANTANA, n. sp. 

 Plate 36, figure 2 

 Type specimen 12299, Coll. Invert. Palae., Univ. Calif., loc. 2169. 

 Shell very small, imperforate; broadly conical; over twice as long as wide; 

 at least five whorls, only four being completely shown; body whorl large, about 

 twice as high as the three preceding ones; whorls slightly convex with an indis- 

 tinct appressed suture; aperture ovate, rounded anteriorly but somewhat pointed 

 posteriorly; outer lip thin, simple; inner lip smooth; shell smooth and polished. 

 Length of type, 4.5 mm.; width of body whorl, about 2 mm. 



This small shell resembles 0. f inornata Whiteaves, from which it 

 differs in its more tumid whorls. 



Horizon. — Chico group, Tellina ooides zone. 



Family Scalidae 

 Genus EPITONIUM Bolten 

 EPITONIUM, sp. 



A single specimen belonging to this genus was obtained at locality 2142. 

 Only five whorls are preserved, neither the base nor the tip being represented. 

 Each whorl is very tumid; ornamented by fine spiral lines and about ten slightly 

 oblique transverse ribs, which are more pronounced along the middle of the 

 whorl, and which alternate on different whorls. 



Horizon.— Chico group, Actaeonella oviformis zone. 



