20 ACANTHOCHITES. 



Girdle produced in front, covered with countless minute whitish 

 glassy spines, and having tufts of hairs at the margins of the valves. 



Length 44, breadth 27? mill. ; divergence 120. 



Japan (Curning Coll., no. 97.) 



This curious shell may be described as a Katharina with the nor- 

 mal tail-plate of Acanthochites, and a pore-bearing girdle. The 

 hairs in the pores are horny, but over the surface white and nearly 

 translucent. ( Cpr.~) 



This species was made the type of Carpenter's subgenus Stectoplax, 

 on account of the valves being two-thirds covered ; but some species 

 of Acanthochites have them even more immersed (such as A. exqui- 

 situs Pi Is.), and others form a perfect transition to the less covered 

 forms. 



A portion of girdle and valves is shown of the natural size in fig. 

 44. Figures 41-44 were drawn by Mr. E. A. Smith from the type 

 in the British Museum. Figs. 36-40 were drawn by Emerton from 

 Carpenter's specimens, collected by Arthur Adams. 



A. CIRCELLATUS Adams & Reeve. PL 2, figs. 53, 54. 



Shell oblong ovate, valves somewhat produced posteriorly, smooth, 

 peculiarly sculptured with circular grooves. Jet black. Ligament 

 densely beset with short bristles spreading over the sides of the 

 valves, and furnished with small tufts of spicules. (five.) 



This is the largest of the tufted species, and quite peculiar in its 

 style of sculpture ; the valves in all others are minutely granulated, 

 but in this they are smooth and characterized by a number of fine 

 grooves radiating in concentric order from the umbones. (Eve.} 



Island of Quelpart, Corean Archipelago (A. Adams.) 



Chiton circellatus Adams & Reeve, REEVE, Conch. Icon., t. 27, f. 

 180 (Oct., 1847.; 



A. SCUTIGER Adams & Reeve. PL 2, figs. 51, 52. 



Shell elongated, narrow ; valves smoothly keeled in the middle, 

 slightly beaked, minutely and very closely granulated ; peculiarly 

 burnt- red color. Ligament densely bristled, spread over the sides 

 of the valves, and furnished with small tufts of spicula. (Reeve.) 



Island of Quelpart, Corean Archipelago (A. Adams.) 



Chiton scutiger Ads. & Rve., REEVE, Conch. Icon., t. 27, f. 178 

 (Oct., 1847). Probably not Acanthochites scutiger ANGAS, P. Z. S. 

 1865, p. 188, and 1867, p. 224. Cf. Cooke, Ann. Mag. N. H. 

 1885, p. 276, and Smith, P. Z. S. 1891, p. 392. 



