86 THE NAUTILUS. 



PARREYSIA NYANGENSIS n. sp. Plate V, upper figures. 



Shell small, elliptical or oval. Epidermis brown, slightly green- 

 ish, shell rather thin, covered with coarse, irregular concentric sul- 

 cations, or corrugations. Post ridge, though very faint, is inclined 

 to be double. Nacre soft, whitish, inclined to pinkish purple in the 

 beak cavities. Muscle scars confluent, not strong. One lateral in 

 the right, two in the left valve. Two cardinals in the right valve, 

 the inner one much the larger. Two cardinals in the left valve, both 

 sulcated. Length 42, height 32, diameter 22 mm. 



This species was collected by Mr. George Schwab, in the Nyang 

 River, March 13, 1913 (Kamerun, Africa). 



Type deposited in the Museum of Comparative Zoology, Cam- 

 bridge, No. 21160. The present species is most nearly allied to the 

 preceding species, Parreysia lobensis nobis. It differs in being more 

 lenticular and higher behind the beaks, and the anterior portion pro- 

 trudes forward more. The exterior is much more coarsely corru- 

 gated, the corrugations being at least three times as large. Its teeth 

 are less split up. 



A NEW GENUS OF TSOCHID^. 



BY WILLIAM HEALEY DALL. 



While working on the Mollusca of the Lightning and Porcupine 

 expeditions in 1883, J. Gwyn Jeffreys described in the Proceedings 

 of the Zoological Society a shell which he called Trochus cancellatus. 

 This was not the Trochus cancellatus of Miinster, and therefore the 

 name must be changed. Moreover no attempt to include this species 

 in a known genus has been satisfactory, and, having found another 

 species in some dredgings from the Galapagos Islands, I propose to 

 name it. 



VETULONIA n. g. 



Shell turbiniform, small, thin, with radiating ribs crossing spiral 

 threads ; umbilicated ; the peristome interrupted by the body whorl ; 

 the outer lip in the completely adult reflected and somewhat thick- 

 ened, the aperture unarmed. 



