CHITON. 217 



A O bl C-TO,5 Ctncc\l o.ttc 



I . 4. C. CANCELLA'TUS * (Leach ?) ,(G. B. Sowerby, Jun) f I 



C. cancettatus, Sow. Descr. Cat. Brit. Chit. p. 4, f. 104, 104 a. b, and 105 ; 

 F. & H. ii. p. 410, pi. lix. f. 3. 



BODY oblong : girdle narrow, irregularly coated with small 

 rather shiny yellowish- white granules; margin closely fringed 

 with short spines. 



SHELL semicylindrical, very convex : plates transversely ob- 

 long and narrow, moderately solid and opaque, and slightly 

 glossy ; each of the middle plates is divided into three distinct 

 compartments (as described in the account of the genus), the 

 lateral compartments in this species being elevated consider- 

 ably above the middle portion, but together scarcely equalling 

 it in superficial area : sculpture) extremely minute round, 

 compressed, and close-set granules, arranged in numerous 

 chain-like rows, which are longitudinal on the first and last 

 plates and on the middle compartment of the other six, and 

 converge to the centre or apex of the triangle in the side com- 

 partments, so as to present a somewhat divaricating appear- 

 ance ; there is no central ridge : colour yellowish- white : beaks 

 inconspicuous, except on the tail-plate : inside glossy, exhibit- 

 ing some of the chain-like sculpture, beside sharp semicircular 

 leaves at each side of all but the head-plate, which form the 

 shoulders of those plates ; margin not notched, but indis- 

 tinctly and microscopically crenulated. L. 0-225. B. 0-125. 



HABITAT : Stones, old shells, and occasionally Ulvce 

 and small sea-weeds in the laminarian zone, Channel 

 Isles, south of England, Isle of Man, north and west of 

 Ireland, Hebrides, and Shetland, at depths between 5 and 

 40 f. ; it is rather local, but not uncommon. Its foreign 

 distribution is wide, and embraces the Norwegian and 

 Swedish coasts from 50 to 150 f., and those of France 

 from E tret at to the Gulf of Lyons. 



Malm found it on Lophelia prolifera. The links of 

 the chain-like rows of granules on this small and pretty 



* Latticed. 

 VOL. III. L 



