'Tusk-shells, Mail-shells, and Limpets i 8 3 



blotches of white, green, or brown. The head-plate 

 has five slight marginal notches, the other plates two 

 each. The orange-coloured foot is oblong 

 in shape, broader in front and running off 

 to a blunt point behind. It may be found 

 all alono: our coasts on the under-side of 

 stones and the face of rocks, stationary and 

 avoiding the light by day, and ranging in 

 search of food by night. Its range extends 

 from low-water mark to about 25 fathoms. 

 The Velvety Mail-shell {C. discrejxcns) is 

 similar in many respects to the former 

 species, but larger and proportionately more slender. 

 The girdle is broader, covered with a dense greyish 

 pile, from Avhich arise tufts of white or reddish 

 spines as in C. fascicular is. Plates shield-shape, 

 one half the width of the animal, greyish, mottled 

 with brown, the keel darker, notches deeper. The 

 two species have the surface of the plates covered 

 with granulations like shagreen ; but in Hanley's 

 Mail-shell (0. hanleyi) the granules become tubercles 

 arranged in lines. There is no distinct keel, and the 

 margins are not notched. The colour is ashy brown. 

 The narrow girdle is clothed with short pale spines, 

 with a tendency to form tufts behind each plate. This 

 is a deep-water species, obtained by trawling at depths 

 between 20 and 80 fathoms. It measures about one- 

 third of an inch. 



The Latticed Mail-shell (('. cancellatus) is very 

 convex, plates narrow, covered with minute round 

 granules, arranged in chain-like rows, the links pro- 

 ducing a lattice-like effect. There is no keel, and the 

 margin is not notched. The colour is very pale 



