194 MAZATLAN UNIVALVES 



Genus LEPIDOPLEUEUS, Bisso. 



II. S( A. Ad. Gen. vol. i. p. 471.— Isclinocliitoii, G-ray, Proe. 

 Zool. Soc. 1847, p. 12G. Mantle scales very minute, grooved : 

 insertion-plates thin, smooth-edged. 



252. Lepidopleueus sanguineus, Rve. 



Chiton sanguineus, Rve. Conch. Ic. pi. 17, f. 98. 



Comp. Chiton limaciformis. Sow. Proe. Zool. Soc. 1832, p. 26 :— 

 Cone/i. III. sp. 58, f. 38.— Rve. Conch. Ic. pi. 8, sp. 42. (Co- 

 lumbia, Sow. : Inner Lobos Is., Peru, and Guacomayo, under 

 stones at low water, Cuming.) 



This is probably not the Ch. sanguineus of Guilding, from 

 St. Vincent's, which is quoted by Eeeve in the Conch. Ic. ; 

 and is certainly not the Ch. sanguineus of Dr. Cutting, from 

 Barbadoes, in the Bristol Museum. It is however identical 

 with the specimens in the Cumingian collection, and most 

 closely resembles Ch. limaciformis. There may be a difference 

 in the integument, whic]i the imperfect state of the specimens 

 has faded to display. The Mazatlah shells are more generally 

 tuberculated on the terminal valves than on the typical speci- 

 mens of the species. 



The mode of attachment is quite different in this shell from 

 that of LophA'rus. The valve margin has an cuter and an 

 inner rim ; the outer being a simi)le continuation of the exter- 

 nal shell layer ; the inner being a white, sharp ridge, cut by 

 10—14 slits in the terminal valves ; so as to give the appear- 

 ance of a lix) with a row of incisor teeth within. The central 

 valves have one slit. The radiating punctiu-es are elongated. 

 Inside roso coloured ; outside brownish i)iuli:, or dark olive 

 green, or brown, or yellowish irregidarly spotted with green. 

 Surface deeply furrowed with irregular longitudinal lines. 

 waved at tlie sharply angular diagonal lines. The terminal 

 valves are tidjcrculose, finely so above, coarsely below. Interior 

 surfiice finely coiTugated and ridged for the muscular attach- 

 ments. Valve lobes small, arched ; sinus very large. The 

 valves are easily loosened from the membrane, which is 

 generally thin and smooth, sometimes with an irregular whitish 

 deposit, apparently not of organic matter. Long. 1'04, lat. "4, 

 div. 105". 

 Hah. — Mazatlan ; verj^ rare ; L'pool Col. 



Tablet 891) contains 4 sp, various colours.— 900, 2 sp. opened 

 to shew the valves. 



