LuciNOPSis. 433 



tlon, may be mentioned Exmouth (Clark) ; Penzance, in 

 twenty fathoms, and Plymouth m twenty-five (M'An- 

 drew and E. F.) ; Torbay and Falmouth (S. H. and 

 Alder) ; Scarborough (Bean) ; Northumberland (Alder) ; 

 Irish Sea (E. F.) ; Hebrides, as at Skye, in from seven- 

 teen to forty fathoms (M'Andrew and E, F.) ; Clyde 

 (Smith) ; St. Magnus Bay, Zetland, in sixty fathoms ; 

 Balta Sound, in from five to ten fathoms ; also in the 

 Moray Frith, fifteen fathoms (M'Andrew) ; in sand at low- 

 water, and also in thirty-five and forty fathoms, Orkneys 

 (Thomas) ; Aberdeenshire (Macgillivray) ; St. Andrews 

 (Knapp) ; Frith of Forth (E. F.) ; " general, around 

 Ireland in suitable localities" (W. Thompson) ; Bantry 

 Bay in fifteen fathoms, and off Cape Clear in sixty fathoms 

 (M'Andrew) ; Birterbuy Bay, Connemara (Barlee). 



This species ranges throughout the Celtic and southern 

 regions of the European seas. Mr. Alder remarks, from a 

 comparison of specimens, that the Artemis compta of Loven 

 is identical with one of our British varieties of it. As a 

 fossil it occurs in both red and coralline crags. 



LUCINOPSIS, Forbes and Hanley. 



Shell more or less orbicular, rather thin, equivalve 

 slightly inequilateral, closed ; surface smoothish or con- 

 centrically striated ; inner margins entire ; muscular im- 

 pressions oblong or suborbicular, nearly equal ; pallial sinus 

 wide, deep, central, obtuse. Hinge composed of two di- 

 verging primary teeth, one of which is bifid, in the right 

 valve, and three, the central one bifid, in the left. Liga- 

 ment external, prominent, rather long ; no defined lunule. 



Animal suborbicular, its mantle freely open, the margins 

 entire. Siphonal tubes short, diverging, separate, the 



VOL. I. ^ K 



