MALACOZOA. GASTEROPODA. CYCLOBRANCHIATA. 183 



Family II. — Chitonixa. 



Animal with the body elliptical or oblong, covered 

 with a shell formed of several distinct transverse plates, 

 adherent to the mantle, which is very thick at the margin, 

 and extends beyond the shell ; the branchiae disposed 

 around the body between it and the mantle ; the head 

 without tentacula or eyes ; the orifice of the anus at the 

 posterior extremity. 



All the species marine, and adherent to rocks, and 

 other bodies, like limpets. 



Genus 1. Chiton. Canoe-Shlll. 



Animal elliptical or oblong, convex, covered by a shell 

 composed of eight transverse pieces ; head destitute of 

 tentacula or eyes ; mouth fleshy, transverse, with a very 

 long tongue armed with minute horny teeth ; stomach 

 membranous ; intestine long, foot very large, elliptical, 

 marginate ; branchiae between the mantle and the body, 

 and consisting of a row of small triangular laminae or 

 protuberances. 



Shell of eight transverse plates, moveable upon each 

 other by means of muscular bands attached to their 

 under surface, and margined with the thickened mantle. 



They live attached to rocks, shells, and other bodies, 

 in the manner of limpets. 



1. Chiton fascicularis. Tufted Canoe-shell. 



Shell elliptical, moderately convex, subcarinate, of eight 

 minutely tuberculate (shagreened) valves, of a dark-grey 

 colour ; the marginal band thick, tuberculate, with eighteen 

 tufts of yellowish hairs, and edged with minute spinelets. 

 Length nearly three-fourths of an inch, breadth about five- 

 twelfths. 



An individual found on the pier of Aberdeen, by Mr. Alex. 

 Davidson, in March, 1842. 



Chiton fascicularis. Linn. S yst. Nat. i. 1 106. — Chiton fascicu- 

 laris. Mont. Test. Brit. 5. — Chiton fascicularis. Flem. Brit. Anim. 

 288. — Chiton fascicularis. Laink. Syst. vi. 321; Ed. 2. vii. 492. 



