POLYPLACOPHORA. Ill 



The sculpture of this very pretty little species resembles the finest 

 lace-work. The shell is rather flat and regularly oval ; the central 

 areas finely and granularly striated; on the lateral and terminal 

 areas the radiating ridges are so regularly intercepted by concentric 

 lines as to present a cancellated appearance. The margin is appar- 

 ently smooth, but the lens discovers very minute sandy granulations ; 

 its color is brown banded with darker patches. The general color 

 of the shell is cream-white variegated with red. (Sowb.) 



Peru (Mus. Cuming.) 



C.fimbriatus SOWB., Mag. of Nat. Hist. 1840, p. 293 ; Conch. 

 Illustr., f. 137. 



Known to me only by the above description and the figures. 



CHITON DIMORPHUS Rochebrune. Vol. XIV, pi. 27, figs. 13, 

 14 (x 3). 



Shell ovate-rounded, umbonate, bright red. Anterior valve wide 

 concentrically lineate. Posterior valve and central and lateral 

 areas of the intermediate valves concentrically sulcate and most 

 minutely puncticulate. The central and lateral areas have quad- 

 rangular pits at their intersections. Marginal ligament rufous, reg- 

 ularly striated with white lines. Length 14, breadth 10 mill. 

 (Rochebr. in Zool. Cap Horn, p. 142, t. 9, f. 10). 



Orange Bay, Patagonia. 



LEPIDOPLEURUS CULLIERETI Rochebrune. Vol. XIV, pi. 8, 

 figs. 78, 79 (x 2). 



Shell ovate elliptical, carinated, buff tawny, maculated with chest- 

 nut. Anterior valve wide, rounded, minutely radiated ; posterior 

 rather small. Intermediate valves having the lateral areas punc- 

 tate, margined with a smooth band; central areas most minutely 

 transversely foveolate. Marginal ligament brown. Length 50, 

 breadth 31 mill. (Rochebr., Zool. Cap Horn, p. 140,t. 9, f. 9). 



Orange Bay; Terra del Fuego. Not common. 



Probably a Chcetopleura. 



CHCETOPLEURA DACRYDIGERA Rochebr. Shell ovate, wide, sub- 

 carinated, olivaceous. Anterior valve, posterior part of the poste- 

 rior valve, and lateral areas of the intermediate valves radially 

 multigranose, the grains elevated, whitish, tear-shaped. Central 

 areas longitudinally ornamented with beaded lines. Marginal liga- 





