Chitones. 101 



4. Chkon ruber. 



C. testa carinata ; valvulis lasvissirais, nitidis ; margine lato, 

 farinoso. 



Valvuli medii dentibus 2. 



Viilvulus l""^ dentibus 9 ; ultimas 10. 



Icon. Tab. nost. V. f. 2.— Chemn. Conch, t. 96. f. 813.— 

 Encyc. Meth. pi. 161. f. ^.— Linn. Trans. VIII. p. 22. N° 6. t. 1. 

 f. 3. (C. cinereus). 



Fabr. p. 423. — Laskey in Wern. Trans. ? 



Colour bright red, or rarely tawny rufous ; mottled. 



On rocks and stones, Oban ; rare. I also found two specimens 

 at Filey, on the Yorkshire coast, on rocks south of the bridge, 

 in the Summer of 1823. 



Shell perfectly smooth and polished, shining; without the least 

 appearance of granulations or punctures under the lens, but 

 marked with irregular, faint, transverse, arched striae of growth, 

 which are obsolete in their transverse, and stronger on their sides 

 in their longitudinal direction. Margin broad as in C. Icevis. 

 Besides these essential differences, it may at once be distinguished 

 from {J. cinereus by its habit and colour, which in all my speci- 

 mens is a bright mottled red or tawny. It is frequently partially 

 encrusted with a black extraneous substance. The fringe is also 

 less distinct than in C. cinereus, and is light red. From C. 

 Icevis it is abundantly distinct, in not having the reticulated mar- 

 gin or granulated valves. 



The figures referred to by Chemnitz, and the Encyc. Meth. are 

 very imperfect in detail, though there are some characteristic 

 marks. That of the Linn. Trans, is excellent. This species has 

 long been involved in much obscurity, and seems to have caused 

 great confusion amongst English writers. It is probably the shell 

 slightly mentioned by Capt. Laskey, and has no doubt been oftea 

 overlooked as a variety of C cinereus. 



5. Chiton Asellus. 



C. testa subcarinata ; valvulis longitudinaliter concatenato-gran- 

 vlosis, vel striis longitudinalibus moniliformibus ; margine granu- 

 Ipso. 



