Wedge-shells, Venus-shells, and Cockles 123 



blue and spotted with pure white; the siphons are 

 as long as the shell, and the mantle is edged with 

 several rows of minute fleshy points. It 

 is a mud -lover and social, and may be 

 found in quantity in bays and estuaries 

 from extreme low water to 40 fathoms. 

 In spite of its dirty surroundings, the shell 

 is always remarkably clean. The siphon- 

 tubes are protected from the mud by a light- 

 brown epidermis. The Peppery Furrow - shell (^. 

 2nperata) is triangular - oval, nearly equal - sided, 

 thin, opaque, flattened, without gloss; the colour 



is greyish white, 

 stained with yel- 

 low or black from 

 contact with the 

 mud ; the epi- 

 dermis glistening. 

 Tlie accompanying 

 f i 2: u 1- e of the 

 hinge-plate in this species will give a good idea of 

 the character prevailing in this group, where the 

 lateral teeth are greatly reduced or wanting. The 

 hinge-plate it will be seen is thick, broad in the 

 centre. There are two cardinal teeth in the right 

 valve, thin, plate-like, and parallel ; 

 in the left valve there is one car- 

 dinal, but often this is double. 

 There are no laterals, but their 

 purpose is served by the ridged 

 sides of the hinge-plate, which keeps the valves from 

 shifting. The animal has a pale yellowish body, the 

 mantle - edge scalloped irregularly and minutely 



Hinge-plate of 

 Peppery Furrow-shell 



