CRETACEOUS FOSSILS. 115 



CYLINDRITES, Morris and Lycett. 



C. BREVIS, n. 8. 

 PI. 29, Pig. 223. 



SHELL short, robust, ovoid; spire low; whorls four, rounded 

 on the upper margin ; suture deep. Aperture broad, produced 

 and rounded in advance ; outer lip simple ; inner lip incrusted ; 

 the incrustation forming a large fold in advance. Sides of the 

 body volution subflattened, approaching anteriorly. Surface 

 marked only by a few indistinct lines of growth. 



Figure, nearly three times natural size. 



Locality : A few specimens have been found by Mr. Mathewson in the vicinity 

 of Martinez. 



This shell is remarkable for its vefy short, robust form, making an outline dif 

 ferent from any other species of the genus with which I am acquainted. As far 

 as I am aware, this is the first species discovered in the Cretaceous formation. 



CHEMNITZIA, D'Orb. 



C. SPILLMANI, Con. ? 



PI. 19, Fig. 70. 



(C. SpiUmani, Con. Jour. Academy of Nat. Sciences Philadelphia, 2 ser., vol. 4, 



p. 287, pi. 46, fig. 48.) 



SHELL elongated, slender; whorls flattened on the sides; suture 

 impressed. Surface marked by slightly curved, obtuse, longitu 

 dinal ribs, crossed by four or five impressed lines ; under surface 

 smooth. Columellar lip thickened. 



Except the difference in size and this is in all probability a young specimen 

 I cannot find a single character on which to separate this shell from Mr. Conrad's 

 species. The difference in the apical angle is not so great as would seem, from a 

 comparison of the figures. The sides, in Mr. Conrad's specimen, are much more 

 nearly parallel than he has represented them. 



Locality: Pence's Kanch, north of Oroville, Butte County (Division A.); col 

 lected by Mr. Brewer. 



