42 ROYAL SOCIETY OF CANADA 
68. TAPES TENERRIMA, Gould and Carpenter. 
Proc. Zool. Soc. London, 1856, p. 200; = Venus rigida, Gould (pars), 1850. 
This fine species is not nearly so common as the last named. I 
have only found it in one locality, namely, Cadboro’ Bay, near Victoria, 
where it occurs in sand between tide marks. Dr. Newcombe has found 
it in a similar situation at Clayoquot Sound. 

In a systematic arrangement our nine species of fresh-water Corbi- 
culide must be placed here. 
They are : 
69. SPHARIUM RHOMBOIDEUM, Say, sp. 
70. — TUMIDUM, Baird. 
7 We Fe SPOKANI, Baird. 
72. S RAYMONDI, J. G, Cooper. 
73. PISIDIUM VARIABILE, Prime. 
74. ABDITUM, Haldeman. 
75. ULTRAMONTANUM, Prime. 
76. ze sp. 
re ss Sp. 
All of the above have been taken by myself on Vancouver Island, 
except S. tumidum and S. Spokani, which were described by Baird from 
localities on the mainland of British Columbia. 
SAXIDOMUS, Conrad. 
78. SAXIDOMUS SQUALIDUS, Deshayes. 
Brit. Mus. Cat. of Veneridæ, p. 188, no. 5 (1853). 
Very common everywhere between tides, and largely used by Indians 
and others as an article of food. 
PETRICOLA, Lamarck. 
79, PETRICOLA CARDITOIDES, Conrad, sp. 
Saxicava carditoides, Conrad, Jour. Acad. Nat. Sci. Phila., vol. vii., pt. 2, p. 258, 
pl. xx., fig. 8 (1837) + Sax. Californica, Conr., op. cit., p. 256, pl. x 
fig. 9. 
This is the name by which this shell has long been known, though 
there appear to be several older ones, e.g.. nivea, Chem., rugosa, Sby., and 
tenuis, Sby. 
Carpenter records it from Puget Sound (Kennerley) and Vancouver 
Island (Swan). Richardson is said to have found four living specimens 
at Victoria in 1875, and Dr. Newcombe obtained young specimens at 
