MARSHALL: ADDITIONS TO ‘ BRITISH CONCHOLOGY.” 361 
from that of Zsocardia; but Jeffreys replies that the 
‘differences observable are perfectly correct, but such 
differences result from altered conditions of growth.” 
The dentition is also different from Jsocardia, which 
Jeffreys ascribes to its being immature. Although I have 
not seen what Jeffreys called his graduated series of the 
young and fry of Zsocardia, 1 believe he has been misled 
by a supposed resemblance between ed/iella and the 
beaks of Jsocardia. 
In his Appendix to ‘ British Conchology,” the author 
describes the alleged Jsocardia fry as “not unlike the 
young of Venus lincta in shape.” It is also much more 
convex, fragile, glossy, and semi-transparent. He has 
also written that they are “nearly globular,” but an 
examination of the beaks of a juvenile /socardia dis- 
proves this. 
Sowerby’s figure of “Kel/ia abysstcola Forbes ; a doubt- 
ful species ; probably a young shell ;” is not this, though 
meant for it, but apparently a decorticated. Axinus ferru- 
ginosus. 
Cyprina islandica L.—St. Aubin’s Bay, Jersey, rare. 
Var. crassior Jeff.—This has the same epidermis and the 
same degree of solidity as the type. Dr. Jeffreys was 
always anxious to give his varieties two characters espe- 
cially, if not three, and this occasionally led him, as I have 
found in many instances, to attach additional characters 
to some of his varieties which had no permanent validity. 
Doggerbank ; Aberdovey ; South Devon coast. Fossil 
in the Belfast deposit, but very rare ; one valve is 5 inches 
broad (Praeger). 
Astarte.—Notwithstanding all that has been written as to the 
specific value of the crenulated margins of the Astarte, a 
respectable body of opinion still supports either side of 
the question. Mr. Edgar Smith has contributed a valu- 
