208 PALEONTOLOGY OF CALIFORNIA. x 



well-marked alternation of larger and smaller ones. Surface of 

 calicle unknown. 



Figure, twice natural size. 



Locality: Division B., near the coal-mines at Mount Diablo. 



Subgen. ELLIPSOSMLLIA, D'Orb. 



? T. GRANULIFERA, n. S. 

 PI. 26, Fig. 196, and 196 a. 



Polypidom trochiform, robust, elliptical above, attached by a 

 broad base ; surface marked by impressed strise, each one cor- 

 responding to the space between two of the septa ; between these 

 striae the surface is finely granulated. Septa thick, not very nu- 

 merous, granular on the sides, as seen from above, narrow on 

 the upper margin. 



Figure, three times natural size. 



Locality : Rare in Division A., near Chico Creek. 



ASTROC(ENIA, E. and H. 



? A. petrosa, n. s. 



PI. 31, Fig. 274, and 274 a. 



Polypidom dendroid and massive, the branches subcylindrical 

 and dichotomous ; cells circular, disposed irregularly, somewhat 

 remote, surrounded by thick walls; columella projecting beyond 

 the edges of the septa, but not reaching as high as the top of the 

 cup. Septa twenty-four in number, thin, somewhat irregular; 

 walls between the cells massive, solid, striated. 



Figures, natural size and magnified. 



Locality : All of the specimens were obtained from a single mass of limestone, 

 a mile west of Martinez. 



