Clark: The San Lorenzo Series of Middle California 165 



Family Solariidae 

 Genus SOLARIUM Lamarck 

 SOLARIUM LORENZOENSIS (Arnold) 

 Architectonica lorenzoensis Arnold. Proc. U. S. Nat. Mus., vol. 34, p. 374, 

 pi. 33, fig. 10, 1908. 



Occurrence. — Pound at University of California locality 3051, at base of Barker 

 formation; associated with Aeila gettysbwrgensis, Solen gravidus, Tellina lorenzo- 

 ensis, Agasoma gravidum, Pseudoperissolax merriami, etc. 



Family CAPUL1DAE 

 Genus CALYPTRAEA Lamarck 

 CALYPTRAEA (GALERUS) cf. EXCENTRICA (Gabb) 



/ Galerus excentricus Gabb, Geol. Surv. Calif., Palaeontology, vol. 1, p. 136, 



pi. 20, fig. 95; pi. 29, fig. 232a, 1857. 

 Calyptrae excentrica Gabb, Clark, Univ. Calif. Publ., Bull. Dept. Geol., 



vol. 9, no. 2, p. 15, 1915. 



CALYPTRAEA RADIANS (Lamarck) 



Crepidula (Trochita) radians Lamarck, Histoire naturelle des Animaux 



sans vertebres, vol. 7, p. 626, 1818-1822. 

 Trochita radians Lamarck, Reeve, Conchologia Iconica, vol. 11, Monograph 



on the genus Trochita, pi. 1, figs. 3a and 3b, 1859. 

 Calyptrae radians Lamarck, Tyron, Man. of Conch., vol. 8, p. 121, pi. 35, 



figs. 84, 88, 1886. 



Trochita radians Lamarck, Arnold, U. S. Geol. Surv., Bull. 322, p. 60, 

 pi. 21, fig. 1, 1907. 



This is one of the few Recent species found in the Agasoma gravi- 

 dum zone. It is very common at University of California locality 

 1131. 



Genus CREPIDULA Lamarck 



CREPIDULA PRAERUPTA Conrad 



Crepidula praerupta Conrad, Geol. U. S. Expl. Exp., p. 727, pi. 19, figs. 9, 

 9a, 1849. 



Crypta praerupta Conrad, Amer. Jour. Conch., vol. 1, p. 151, 1865. 



? Crepidula praerupta Conrad, Anderson, Proc. Calif. Acad. Sci., ser. 4, 



vol. 2, no. 2, p. 204, pi. 16, figs. 68, 69, 1905. 

 Crepidula praerupta Conrad, Dall, U. S. Geol. Surv., Prof, paper no. 59, 



p. 83, pi. 7, fig. 8, 1909. 

 Crepidula praerupta Conrad, Arnold and Hannibal, Proc. Amer. Philos. 



Soc, vol. 52, pp. 476, 583, 588, 1913. 

 Crepidula praerupta Conrad, Clark, Univ. Calif. Publ., Bull. Dept. Geol., 



vol. 9, no. 2, p. 15, 1915. 



