INSTITUTE OF SCIENCE, PHILADELPHIA. 245 



Subgenus Sthenorytis Conrad. 



Scala (Sthenorytis) Stearnsii Dall. 



Plate 21, figure 4. 



Pliocene of San Diego, California, Dr. R. E. C. Stearns. 



Shell large, stout, short conical, of about six whorls (the specimen hav- 

 ing lost its apex, the exact number is doubtful) ; each whorl provided with 

 about seven strong reflected varices, slightly angulated near the suture, where 

 each varix is appressed against the interspace and corresponding varix of the 

 antecedent whorl, forming a wave in the varical contour; varices very thick, 

 sharp-edged, somewhat rugose from the prominence of the incremental lines, 

 on the base overlapping one another, and on the spire continuous over the 

 whorls to the apex ; surface smooth, except for lines of growth ; a faint indi- 

 cation of a basal cingulum is perceptible in one or two of the intervarical 

 spaces ; suture filled by the appressed varices ; whorls very round, aperture 

 nearly circular, except for the sutural wave. Lon. (of decollate shell 2^^ 

 whorls) 26; max. lat. 25 mm. 



It was thought best in treating of the Pliocene fauna to introduce here 

 this magnificent species, of which a single specimen was collected by Dr. R. 

 E. C. Stearns from the Pliocene sands of Pacific Beach, near San Diego, 

 California. It indicates the extension of the genus already known from the 

 Miocene of Maryland and Santo Domingo, to the Pacific Coast, in a fauna 

 where several remarkable Scalidce {Opalia anomala and varicostata Stearns) 

 are already known. 



The figure given has the upper outer part of the peristome somewhat 

 restored, and gives, perhaps, a somewhat too rounded aspect to the varix re- 

 flection ; and the wave in the same, where it is appressed between the varices 

 of the antecedent whorl, is more pronounced than seems to be normal, though 

 in this respect it represents the fossil fairly well, but the preceding varices 

 are more gently waved. 



Family EULIMID^ (supplementary). 



Genus NISO Risso. 



Niso lineata Conrad. 



Plate 20, figure 4. 



Bonellia lineata Conrad, Journ. Acad. Nat. Sci. Phila. viii. p. 1S8, 1842. 



Acttson simplex H. C. Lea, Trans. Am. Phil. Soc, 2d ser. ix. p. 32, pi. 36, fig. 62, 1845 J 



fide Conrad. 

 Niso lineata Conr. Proc. Acad. Nat. Sci. for 1862, p. 566 ; Am. Journ. Conch, ii. p. 69, pi. 



4, fig. 13, 1866 (bad!). 



Chesapeake Miocene of Calvert Clififs, Maryland, Conrad ; and Cape 

 Fear River, North Carolina, at Mrs. Guion's marl-bed, C. W. Johnson. 



Shell differing from N. interrupta in being less slender, especially toward 

 the tip of the spire, in the more distinct suture and convex whorls, and from 



