— 39 — 

 CRETACEOUS AND EOCENE (CRET. B) FOSSILS. 



Terebra wattsiana n. sp. (PL I, Fig. 1.) 



Whorls regularly tapering, about fourteen (upper three or four lost); 

 flattened, slightly turreted by narrowing in front, the highest with 

 about t\yenty-three narrow, close-set riblets crossing their whole width 

 vertically, and increasing to about fifty on body-whorl. Base and 

 columella smooth, mouth normal, canal much twisted, notch deep. 

 Length, about 1.75 inch; breadth, 0.45; mouth, 0.4; width, 0.10. More 

 robust, larger, and fewer-whorled than T. californica Gabb, also of 

 Div. B, but nearly allied to that species. A single specimen only was 

 found at Marysville Buttes by Mr. W. L. Watts. 



Surcula crenatospira n. sp. (PL I, Figs. 2, 3, 4.) 



Nuclear whorls three, smooth, large, the apical immersed; other 

 spiral whorls five, turreted, gradually enlarging, each with about nine 

 rounded tubercles horizontally flattened, forming a chain around the 

 middle, and connected by two strong revolving ribs, making a sharp 

 angle. Above this are five or six fainter ribs, crossed by strong sinuated 

 lines of growth, and below a similar sculpture, the whole surface being 

 thus divided by strong reticulations, extending forward on body-whorl 

 about half its length. Mouth simple, sinus moderate above angle, 

 canal long, straight, aperture as long as spire. Length, about 1.75 inch; 

 breadth, 0.80; mouth and canal, 1 inch long, 0.40 wide. 



Not very near any of Gabb's species of the family, except in the 

 long canal, which seems to have been more common in the fossil than 

 in living Pleurotomidee . The character of the sinus and sculpture ally 

 this and some of the following to the sub-genus Clathurella, though 

 according to those who classify by the soft parts, such divisions are of 

 little value. They must be taken for all they are worth in fossil species, 

 as necessary divisions, in the absence of better ones. 



Quite common at Marysville Buttes, where Mr. Watts and Mr. 

 Ullrey obtained 35 specimens. . A very similar species inhabits the 

 West Coast of Mexico at present (S. olivacea Shy.). 



Surcula monilifera n. sp. (PL II, Figs. 28, 29.) 



Fusiform; nuclear whorls three, smooth, conical; the next crossed 

 by twelve or more strong, oblique riblets, which change on fourth or 

 fifth into a row of beaded knobs, forming an angle along middle of 

 whorls, increasing to thirty-five on ninth or body-whorl. Above this 

 angle are nine or ten fine revolving riblets, and three or four below it, 

 the two posterior being longest, and imperfectly beaded at the suture. 

 On the anterior whorls the medial knobs are sometimes doubled, and 

 on the body-whorl the revolving riblets are alternately large and 



