APPENDIX. 36.5 



simis, lunula nulla, extus lutescente seu albidi-olivacea, 

 intus alba, marginibus tenuissime crenulatis ; sinu pallii 

 brevi, obtusa. 



This shell was taken in considerable numbers from 

 the crop of a pin-tail duck, shot in the harbour of 

 Esquimalt, Vancouver Island. 



It is a small species, of an ovate-triangular shape, a 

 smooth shining appearance, and a light olive colour. 

 The surface is concentrically marked with slight grooves. 

 The beaks are prominent and very shining. Internally 

 the surface is white, the margins of the shell very finely 

 crenulate, and the pallial impression short and blunt. 

 Long, nearly inch; lat. rather less than inch. 

 Hob. Esquimalt Harbour, Vancouver Island. (Brit. 

 Mus.) 



"Venus rigida. (Gould.) Vancouver Island, mud between tide marks. 

 Saxidomus squalidus. (Desh.) Vancouver Island, mud between tide 

 marks. 



Sphcerium (Cyclas) tumidum. (Baird: Nov. Sp.) 



Testa ovato-trigona, tumida, olivacea, conferte 

 transversim concentrice forte costata; umbonibus pro- 

 minentibus, necnon erosis ; interne cserulescente ; mar- 

 gine ventrali rotundato. 



This shell is of a tumid, swollen figure, and of an 

 ovate-trigonal shape. The colour externally is dark 

 olive, and it is strongly ribbed concentrically. The 

 beaks are prominent, and frequently eroded. The inner 

 surface is of a bluish tint. The ventral or lower margin 

 is rounded. Long. % inch ; lat. rather more than ^ inch. 

 Hab. Sumass Prairie, Fraser River, British Columbia. 

 (Brit. Mus.} 



