32 ROYAL SOCIETY OF CANADA 
31. Nucuta TENUIS, Montagu, sp. 
Arca tenuis, Mont., Test. Brit., Suppl. p. 56, pl. xxix., fig. 1 (1808). © 
uLkCs 
Occurs with the last named species, but is not quite so common. 
LEDA, Schumacher. 
. 32. Lepa Fossa, Baird. 
Proc. Zool. Soe. London, 1863, p. 71. 
This species was described from a single specimen taken by Dr. 
Lyall in Esquimalt Harbour. It was also represented by a single 
specimen in Dr. Kennerley’s collection. 
Though Z. fossa is very abundant in the “ Leda clay” of Victoria, 
I have never succeeded in finding recent specimens. Mr. Whiteaves 
records with a query “a single worn valve,” Duncan Bay, V.I. (Dr. 
Dawson. ) 
33. Lena minuta, Müller, sp. 
Arca minuta, Müll., Prodr. Zool. Dan., p. 247, no. 2985 (1776). 
This is the common Leda at Victoria and northward to the Queen 
Charlotte Islands. It is much smaller than L. fossa, and its sculpture is 
quite different. I have not yet found this species in the Leda clay. 
34. Lepa acuta, Conrad. 
= ? L. celata, Hinds. 
= ? L. cuneata, Sby. 
There is certainly a third species of Leda in our seas, but I am not 
sure what it should be named. Mr. Whiteaves, in his paper on the 
Queen Charlotte Islands Mollusca, records a single valve from Houston- 
Stewart Channel as J. cœlata, Hinds. 
In his next paper (Trans. Roy. Soc. Can., 1886) he refers ten shells 
of the same species from Quatsino Sound to L. acuta, but suggests, 
quoting Drs. Dall and Cooper, that acuta, Conrad, celata, Hinds, and 
cuneata, Sby., are one and the same species. I have not access to the 
literature or specimens necessary to a decision on such a point, and 
therefore follow Whiteaves in adopting the name Z. acuta, but I may 
say that the shells from Quatsino Sound above mentioned are not con- 
specific, in my opinion, with some received as L. acuta from California 
(Hemphill). 
YOLDIA, Moller. 
35. YOLDIA THRACIÆFORMIS, Storer, sp. 
Nucula thracieformis, Storer, Bost. Jour. Nat. Hist., vol. ii., no. 1, p. 122, figure (1838). 
Two small living specimens, Forward Inlet, Quatsino Sound, Dr. 
Dawson. 
