ISCHNOCHITONIDAE 



319 



fly-shaped valves are completely covered by the large, leathery, firm girdle 

 which is reddish brown to yellowish brown. Minute red spicules make 

 the girdle feel gritty. Common in the northern part of its range. Formerly 

 called Cryptochiton stelleri. 



Figure 67. Atlantic Coast chitons, showing from the underside the position and 

 length of gills and the nature of the lappets, a, Ceratozona nigosa Sby., i to 2 

 inches; b, Cryptoconchns floridaniis Dall, i inch; c, Calloplax jajieirejisis Gray, 

 % inch; d, Chaetopleura apiculata Say, % inch; e, Tojiicia schranmti Shuttleworth, 

 I inch; f, Chitoji tuber ciilata Linne, 3 inches. 



Family ISCHNOCHITONIDAE 



Genus Calloplax Thiele 1909 



Rio Janeiro Chiton 



Figure 67c 



Calloplax janeirensis Gray 



Lower Florida Keys and the West Indies. Brazil. 



% to % inch in length, oblong, gray to greenish brown, or speckled 

 with red. Very strongly sculptured. Lateral areas strongly elevated by 

 3 to 4 very coarse, large, beaded ribs; anterior valve with 12 to 18 such ribs. 

 Central ridge (or jugal tract) with longitudinal rows of fine beads; apex 

 elevated, smooth and rounded. Central area with about 1 2 very sharp, gran- 

 ulose, longitudinal ribs. Interior white. Anterior valve with i o, middle valves 

 with I and posterior valve with 9 slits. Girdle with very fine "sugary" 

 scales and an occasional single hair. Gills start Ys the way back from the head 

 and extend posteriorly to a large, fleshy lappet on the posterior margin of 

 the girdle. An uncommon species. 



Genus Chaetopleura Shuttleworth 1853 

 Chaetopleura apiculata Say Common Eastern Chiton 



Figures 6-jd\ 68 



Cape Cod, Massachusetts, to both sides of Florida. 



% to % inch in length, oblong to oval. Valves slightly carinate. Central 



