84 PECTINID-E. 



valve now before me, one of the ears is twice the size of 

 the other. The fry, — th of an inch long, are roundish- 

 oval and distinctly ribbed. 



L. subauriculata differs from L. elliptica in the shell 

 being more arched or equally convex throughout, as 

 well as much smaller and longer ; the sculpture is coarser 

 and the ribs fewer; the ears are smaller and droop a 

 little; and the furrow is straight and placed in the 

 middle. In the other species the shell is considerably 

 broader and more expanded ; the sculpture is finer and 

 the ribs more numerous ; the ears are larger and more 

 erect; and the furrow runs obliquely, and is placed 

 somewhat nearer to the posterior margin. The young 

 of each species have corresponding characters. That 

 of L. elliptica resembles L. Sarsii in shape, but differs 

 toto ccelo in the sculpture and in having a conspicuous 

 furrow. 



The present species is the L. sulcata (" Leach ") of 

 M oiler, L. elongata of Forbes, L. subauricula of Phi- 

 lippi, L. sulculus (" Leach ") of Loven, andL. unicostata 

 of Leach's posthumous work on the Mollusca of Great 

 Britain. I at one time thought it might also be the 

 Ostrea nivea of Renier, which has been well described 

 and figured by Brocchi. But although our shell is found 

 in the Adriatic, and may therefore have been the species 

 intended by Renier, I do not believe it occurs in the 

 Subapennine tertiaries, so as to have fallen under 

 Brocchi's observation ; and neither of these authors has 

 noticed the central groove or furrow, which is so charac- 

 teristic of this species and L. elliptica. The Ostrea 

 subauriculata of Turton's ' Conchological Dictionary ' 

 appears to have been the young of L. Loscombii, judging 

 from his description and specimens. 



