336 Mr. A. Hancock on Shells dredged on 



deep visceral depression in the centre of the shell being sufficient 

 to determine the species. 



This shell was taken in great profusion. 



Astarte Warhami, n. s. PI. V. fig. 15, 16. 



Shell thin, elliptical, ventricose, with about sixty fine, close, 

 sharp, regular, concentric ribs ; ends equally rounded ; umbones 

 rather prominent, nearly central; anterior end well-produced, 

 with the slope concave; lunule not very deep, oblong-ovate; 

 posterior end slightly convex with the depression lanceolate; 

 basal margin entire, well and regularly arched ; epidermis glossy, 

 pale greenish yellow; inside bluish white. Length f inch; 

 breadth nearly 1 inch; depth T 7 ^ inch. 



It would appear that this, one of the prettiest and most deli- 

 cate of the genus, is not at all common ; only six specimens were 

 obtained. It is paler and brighter than is usual with the Astartes, 

 and is generally marked with a few irregular dark blotches or 

 spots, probably caused by injuries sustained by the shell. In old 

 specimens the ribs blend at the basal margin, where the epi- 

 dermis is rather coarse and wrinkled. 



This species is not likely to be confounded with any other, 

 though it has some general resemblance to Astarte elliptica ; it 

 is however more regularly oval and more ventricose, the colour 

 is brighter, and the surface more glossy. It is perhaps more 

 closely allied to the A. Laurentiana of Lyell, a fossil species ob- 

 tained from the glacial beds of Canada, but differs from it in 

 having the ends more equally rounded, and in the position of the 

 beaks, which in that species are placed considerably towards the 

 anterior end; the prominent lateral teeth are also wanting in 

 A, Warhami. 



This species is named in honour of Mr. Warham, the gentle- 

 man to whom I am principally indebted for this interesting col- 

 lection of Arctic shells. 



Cardium Grcenlandicum, Chemnitz. 

 Cardium Grcenlandicum, Chemn. Conch, vol. vi. t. 19. f. 198. 

 Venus Islandica, O. Fabr. Fauna Grcenl. p. 411. 

 Cardium edentulum, Montagu, Brit. Shells, Supp. p. 29. 



Two or three fine fresh specimens were brought, and several 

 single valves occurred, some of which measure nearly three inches 

 in breadth. A young individual was also procured ; it is very 

 delicate, is more distinctly ribbed than the mature shell, and is 

 prettily marked with zigzag lines of a pale fawn-colour. 



Cardium Islandicum, Chemnitz. 

 Cardium Islandicum, Chemn. vol. vi. p. 200. t. 19. f. 195, 196. 

 Cardium ciliatum, O. Fabr. Fauna Grcenl. p. 410. 



Two specimens were dredged ; one is in fine condition : it is a 



