MARSHALL: ADDITIONS TO “ BRITISH CONCHOLOGY.” 367 
time, and is now bidding fair to compete with the familiar 
cockle. This fine Venus is commonly known in America 
as the ‘clam,’ and is of course an edible species. A 
number of shells dredged from the river were exhibited 
by Mr. J. R. Hardy at the Manchester Conchological 
Meeting.”—Manchester City News, March 23, 18809. 
Tapes aureus Gm.——This is more variable than any of its 
congeners. I have them of every degree of convexity and 
compression. ‘The prettiest come from Scilly, and the 
largest from Guernsey ; one from the !atter island is just 
under two inches broad. Occasionally it is pink inside, 
like Z. wzrgineus, and more rarely the inside margins are 
deep purple. 
Var. quadrata Jeff— Herm Island; Helford River, Corn- 
wall ; Weymouth. 
Var. ovata Jeff—Herm Island. 
T. virgineus L.—Very young specimens are squarish, 
and the fry nearly circular. I have a monstrosity from 
Guernsey analogous to a similar form of 7. aureus from 
the Turton collection, having ‘an oblique fold extending 
from the umbonal area to the front towards the posterior 
side.” 
Var. sarniensis L.-—Scilly (Smart and others). 
Var. elongata Jeff.—Guernsey. 
T. pullastra var. ovata Jeff.—Guernsey ; Torbay. 
Var. oblonga Jeff.—Guernsey. 
T. decussatus var. quadrangula Jeff—Torbay ; Dawlish. 
Lucinopsis undata Penn.—Dr. Jeffreys writes of this in the 
‘ Lightning’ Report : “It is difficult to distinguish this from 
Diplodonta rotundata except by the hinge ;” but no diffi- 
culty need arise if it is remembered that this is a chalky- 
white shell, fragile, and brittle, while Dzplodonta is glassy- 
white, and not easily broken. The animal is very handsome, 
snowy-white, with orange tubes; it will live for several days 
