PHYLLIDIANA. MOLLUSCA. CHITON. 149 



This very beautifully marked species varies considerably in outline, 

 size, marking, and color. Some have the sides nearly parallel, and 

 others are decidedly ovate ; some exceed an inch in length ; some 

 have the lines of growth deeply marked, while others are nearly 

 smooth ; some have a dead, ashen color, but such are apparently very 

 old. In some the zigzag lines and white dots are very distinct, in 

 others not. 



This may very probably prove identical with some species of the 

 North of Europe ; but as it is utterly impossible to say which one, I 

 will not run the risk of adding further confusion to the already inex- 

 tricable synonymy of the Chitons, by offering any conjectures. Dr. 

 Loven says, "It is a very common species with us [in Sweden]. I 

 think it is the S. Icsvigatus^ Fleming." Mr. Sowerby thinks " it would 

 be impossible to find a distinguishing character" between this and C. 

 cinereus. In this he is certainly mistaken. It comes much nearer to 

 his red variety of C. marginatus ; but the granulations of the surface of 

 our shell are not half so distinct as in either C. marginatus or C. cine- 

 reus. It is, therefore, best to use Mr. Couthouy's name for the pres- 

 ent, as it is the only one to which the shell can now, or perhaps ever, 

 be referred with certainty. 



Chiton ruber. 



Shell small, oval, elevated, carinated ; valves marJced by lines 

 of groivth; otherwise smooth, strongly beaked; margin pulveru- 

 lent, red and white. 



Figure 24. 



State Coll., No. 166. Soc. Cab., No. 2352. 



Chiton ruber, Lowe ; Zool. Journ., ii. 101, pi. 5, f. 2. Sowerby; Conch. Illust., 

 f. 103, 104, lower fig. Fleming ; Edin. Encyc, vi. 102. Brit. Anim., 289. 



Shell small, strong, nearly oval, being but slightly narrowed be- 

 fore, convexly elevated and traversed by an elevated ridge or keel 

 along the back ; valves without any appearance of granulations or 

 punctures under the magnifier, but marked with conspicuous 

 grooves, indicating the stages of growth, most marked near the 

 border ; otherwise perfectly smooth, shining, and polished ; pos- 

 terior margin strongly beaked. Color, light brick-red or flesh- 

 color, with occasional dashes of dark crimson across one or more 



