I Q2 



BY THE DEEP SEA. 



RAYED ARTEMIS. 



On the same sand and pebble beaches we shall find in 

 greater plenty another of the Venus shells, the Rayed Artemis 

 (Artemis exoleta). We presume that Linnaeus, in giving this 

 species its name of exoleta (Latin, 

 worn-out), was struck by the fact 

 that however fresh a specimen may 

 be, it has the appearance of having 

 been knocking about with sand and 

 shingle for some time. The shells 

 are white, with variable rays of 

 pinky-brown (sometimes entirely ab- 

 sent), and finely and evenly marked 

 with concentric grooves. In propor- 

 tion to its size, it is a very thick shell ; 

 very round in outline, except that a piece appears to have 

 been nicked out of the edge in front of the beak. When the 

 shell is closed, these marks on the two valves, coming together, 

 form a heart-shaped depression of a brown tint, and called 

 the lunule. 



The lunule is not peculiar to this species, but is shared 

 by a large number of bivalves. It is well-marked in the 

 Smooth Venus, but not so completely heart-shaped as in the 

 Rayed Artemis. There is a finely-developed set of hinge- 

 teeth, and the pallial impression is deeply sunk. A closely 

 allied species, the Smooth Artemis (A. lincta), is smaller, not 

 banded, and the concentric ridges are finer and less perceptible. 

 It is this peculiar type of smoothness that suggested the specific 

 name vilincta (Latin, sucked), its appearance being as though 

 a specimen of exoleta had been sucked until smooth. Both 

 these have a hatchet-shaped foot for digging into the sand. 

 Great quantities of this bivalve are washed up in winter, and 

 I have frequently come across a piece of rock protruding 

 through the sand, around which there were dozens of these 

 shells, broken or chipped, giving evidence, from their fresh 

 muscles, that they had but recently been destoyed. It has 



