8 CHITON. 



neral colour fawn or tawny, perfect shells deepest on the 

 back, worn shells white at the apex of each valve. 



Gmelin has referred this species to C. aculeatus, to 

 which it has no affinity, but he has added a note of 

 interrogation. 



The subject represented in the Plate was brought 

 from Portugal, but was probably taken in South Ame- 

 rica. 



PITCHY CHITON. 

 PL 1. /. 3. Dr. Coombe. 



4. Chiton piceus. Ch. testa octovalvi, supra glabra picea, nigro albidoque 



varia. Linn. Gmel. p. 3205. 

 Shell of eight valves, upper surface smooth, pitchy, varied with white 



and black. 

 Chem. Conch. 8. t. 96. f. 807—810. Chem. Chiton, t. 2. f. 6. Encyclop. 



Method, pi. 163. f. 3, 4, 5. 



Chemnitz considers this species as a variety of the fol- 

 lowing, or granulatus, but its affinity lies in the margin 

 only, which in both is coriaceous and spiny : in other 

 particulars they differ essentially. The valves of the 

 pitchy Chiton are rude and mishapen, with a smooth 

 black band running along the back, and separated from 

 the marginal division, on each side, by a broad white 

 line. Near the margin the valves are dark, scaly, and 

 covered with pitchy granulations. The shell within 

 is black in the middle, the sides greenish. 



This species inhabits the Red Sea, and American 

 ocean. It is said sometimes, though rarely, to be found 

 with six or seven valves. 



