292 CERATOZONA. 



coarse, but the more delicate ones are easily lost. The pore-bunches 

 at the sutures are rarely conspicuous, and often cannot be made out 

 without the aid of a lens and a lively imagination ; and this fact 

 somewhat impairs their value as a generic character. Nearly all of 

 the adult specimens I have seen are very much eroded. 



Some recent authors have used the name guildingi Reeve, for 

 this species ; it is not easy to see why, for Sowerby and Adams both 

 preceded the author of the Iconica. The original figure of guildingi 

 is copied on my plate, fig. 37. The sculpture varies a good deal. 

 Fig. 36 is drawn from one of the most strongly sculptured speci- 

 mens I have seen, from Jupiter Inlet, Fla. Fig. 34 is from Sta. 

 Cruz., of the Virgin group, being drawn from a specimen colored, 

 exactly like Sowerby's original figure of rugosus (fig. 33). In this 

 shell the teeth are less propped and the eaves narrower than in the 

 Florida examples. Fig. 35 is from a Jamaica specimen. 



I have seen no specimen with the mucro so posterior as it is shown 

 in Carpenter's figure (fig. 41) ; all I have seen resemble fig. 39. 



C. SETOSA Sowerby. PI. 61, figs. 40, 38, 39. 



Shell oblong-oval, ashy-greenish, scabrous; front valve, lateral 

 areas and posterior valve radially sulcate. Marginal ligament 

 setose, the setae rather short and close. 



Length 32i, breadth 15 mill. (Sowb). 



Guacomayo, Central America (Cuming). 



Chiton setosus SOWB., P. Z. S. 1832, p. 27 ; Conch. Illustr. f. 19. 

 REEVE, Conch. Icon., f. 100. Not C. setosus Beechey's Voy. 

 ' Blossom ' t. 41. f. 17,=Mopalia. Not Ch. setosus Tiles, Mem. Ac. 

 S. Pet. ix, p. 484 (1824). 



This species is very distinct from C. setiger King, which it in some 

 degree resembles. The bristles around the edge are much shorter,, 

 thicker and more closely set. (Sowb). 



Carpenter has had figures of the interior and tail valve prepared^ 

 and I have copied them in my figs. 38, 39. I have seen no species 

 of this sort from the Pacific side of the isthmus, and I am therefore 

 not prepared to say what relation setosa sustains toward rugosa, the 

 West Indian form. Fig. 40 is a copy of Sowerby's original figure 

 of setosus. 



