72 ROYAL SOCIETY OF CANADA 



240. OciNEBRA INTERFOSSA. Curpcnter. 

 J{e])t. Brit. Assoc, 18(W, p. (MW (August, 18(54); and Pioc. Acad. Nut. Sei. Phila., 



186.5, p. m. 



Both the above are common littoral shells, occurring all through 

 therprovince under stones, near low water mark. Both are subject to 

 considerable variation. 



CEEOSTOMA, Conrad. 



241. Cerostoma poliatum, Martyn, sp. 



Purpura folidta, Martyn, Univ. Conch., vol. ii., no. (>H. pi. xxiv., fig. 1 (1784). 

 = Mure.v foUatus, Gmelin. 

 = M. monodon, Esch., 

 etc., etc. 



At extreme low tide on all our rockj^ coasts. 

 PUEPUEA, Brugui^re. 



242. Purpura crispata, Chemnitz, sp. 



BifcriiiKiii (ri.spntuiii, Clieni., Mart. Conch. Cab., vol. xi., p. 84, pi. 187, figs. 1802, 1808 



(1795). 

 = M. lactuca and 31. ferrugineus, Esch. (1829). 

 etc., etc. 



243, Purpura lima, Martyn, sp. 



Bncrimantuiia, Mart., Univ. Conch., vol. ii., no. 46, pi. xv,, fig. ] (1784). 

 = canallcnlata, Duclos (1832). 

 = dccemvoKfato. Midd. (1849). 



244. Purpura saxicola, Valenciennes. 



Zool. Voy. Venus, pi. viii., fig. 4 and 4a (1846). 



These three species of Purpura are all common on rocks between 

 tides and here at any i-ate are quite distinct from one another in all their 

 varieties. 



From some few localities these shells are absent without any appar- 

 ent cause. For instance, during three days shore collecting at jS'anaimo 

 last year. I did not see a single specimen of either lima or saxicola and 

 only in one spot a few specimens oi' crispata. 



There are conchologists who would place all these species under one 

 name and there are others who would consider even this a synonym of 

 the Purpura lapillus of the Atlantic. Many varieties of P. saxicola have 

 been honoured with separate names, which however are hardly worth 

 preserving. 



