76 KELLIAD^. 



inflected, oblique, and one of them tolerably prominent. 

 The interior is white and glossy, and the margin simple. 

 The hinge consists, in the left valve, of an apical laminar 

 tooth on each side of the beak, each diverging widely 

 from the other, and separated by a wide triangular cavity. 

 The hinder tooth is by far the larger, and both are absent 

 in the edentulous right valve, which, however, presents 

 much resemblance to the other, from the margins themselves 

 on either side of the still broader triangular cavity being 

 elevated so as to resemble lamina?, but not like the teeth 

 of the other valve, distinctly divided from the rest of the 

 dorsal margin, by an intervening sulcus. Professor Loven 

 has detected a rudimentary ossicle, which appears to Mr. 

 Alder, who has likewise observed it in British examples, 

 a mere calcification of the lower part of the ligament. It 

 is so easily detached that very few cabinet specimens ever 

 exhibit it. The length of the shell is half as large again 

 as the breadth, and at the very most is but a quarter of an 

 inch, but rarely, indeed, attains to much more than half 

 that measurement. 



A sketch, communicated by Mr. Alder, represents the 

 animal extending its large and broad foot from the longer 

 extremity, but presenting no traces of siphonal tubes. 

 This is a well- diffused species, but never a very common 

 one, indeed, pairs are very scarce, and even single valves, 

 except locally, are not plentiful. It is generally found 

 burrowing in very thick valves of dead oysters. It is 

 taken at Oullercoats, near Newcastle (Alder) ; Scarborough 

 (Bean) ; Weymouth (Jeffreys) ; Salcomb Bay (Mont.) ; 

 Liverpool (M' Andrew). In Wales, at Tenby (Lyons and 

 S. H.) ; Oxwich Bay, near Swansea (Jeffreys). Belfast 

 Bay extremely rare, and Dublin Bay (W. Thompson) ; 

 Portniarnock, Bantry Bay, and Cork Harbour (Hum- 



