CHITON. 411 



The granules of the lateral triangles, whose shagreening is 

 occasionally almost obsolete, scarcely display any radiating 

 arrangement ; the longitudinal ones of the central areas 

 are rather oblique, and somewhat rhomboidal in shape ; 

 the series are so closely disposed that the punctured 

 interstices are more conspicuous than the raised sculp- 

 ture, from the grains being comparatively large, flat, and 

 touching, so as almost to present a level surface. When 

 highly magnified, the somewhat oblique longitudinal inter- 

 stices appear to be decussated, lattice or diamond fashion, 

 by still finer striulaj, whence probably the name cancellatus 

 has been derived. 



Our largest examples are not a quarter of an inch in 

 length, and hardly exceed an eighth of an inch in breadth. 



The C. alveolus of Sars, judging from Loven's descrip- 

 tion (Ind. Moll. Scand. p. 27), must bear some resemblance 

 to this species, and Payraudeau''s figure of his G. Bissoi 

 (Moll. Corse, p. 87, pi. 3, f. 4, 5) reminds one not a little 

 of its form and sculpture. 



In about eight to ten fathoms, St. Peter's Port, Guern- 

 sey; Weymouth and South Devon (S. H.) In fifteen 

 fathoms off Douglas Bay, Isle of Man (E. F.); Oban, 

 fifteen fathoms ; in fifteen to twenty fathoms near land, 

 Zetland ; and in forty fathoms in a tideway off Fitful 

 Head (M'Andrew and E. F.) ; Loch Carron and adjacent 

 lochs, in ten to twenty fathoms (Jeffreys). 



0. L^vis, Pennant (?). 



Much elevated, narrow, red ; ligament reticulated. 



Plate LVIII. fig. 3. 



Chiton IcEvis, Pennant, Brit. Zool. ed. 4, vol. iv. p. 72, pi. 36, f. 3 (proljiibly). — 

 Mont. Test. Brit. p. '2, — Maton and Rack. Trans. Linn. Soc. 



