POLYPLACOPHORA. 105 



reported tulipa from Port Lincoln, P. Z. S. 1865, p. 186. His 

 species can hardly be the true tulipa however. 



CHITON ELONGATUS Blainville. Body quite long, narrow, convex, 

 rounded equally at the two extremities, not carinated ; the end 

 valves sensibly smaller proportionally than in the preceding species, 

 but still alike. Anterior valve tuberculose throughout the greater 

 part of its extent, its border of insertion divided into 15 very short 

 teeth, not pectinated ; posterior valve short with 11 teeth, not at all 

 pectinated ; the lateral areas of the intermediate valves are quite per- 

 ceptible ; the margin subsquamose ; color extremely variable, green 

 on each side, the middle of the back yellowish-white. (Blainv., 

 Diet. Sc. Nat. xxxvi, p. 542). 



Seas of Australia (Per on & Lesueur). 



Apparently an Ischnochiton, but certainly not determinate. 



CHITON LINEOLATUS Blainv. Body oval, quite long, the lateral 

 areas of the intermediate valves less distinct than in the preceding 

 species [C. pictus Blv.] and having numerous stria3 at the borders ; 

 the scales of the girdle very small ; the teeth of insertion not pectin- 

 ated. Color varied with small longitudinal brown spots on a yellow- 

 ish ground. (Blainv 1. c., p. 541.) 



Island of King (Peron and Lesueur). 



CHITON ALBIDUS Blainv. Body oval, thick, quite depressed ; 

 the girdle moderate and covered with short and very fine hairs. 

 Shell large, 8-valved, proportioned nearly as in the preceding 

 species [C*. hirtosus]; the lateral areas of the intermediate valves 

 a little indicated by a plane surface, and bordered by some striae of 

 growth. Anterior valve festooned on its margin of adhesion, divided 

 into 9 large and entire teeth ; the posterior valve without slits in its 

 plate of insertion. Color of girdle uniform gray-brown ; shell soiled 

 white, or grayish below, of an aqua-marine green within. (Blainv., 

 Diet. Sc. Nat. xxxvi, p. 547). 



Seas of the Island of King. 



This is evidently a Plaxiphora. 



CHITON COSTATUS Blainv. Body oval, wider in the middle than 

 at the ends ; girdle covered with quite long hairs. Shell subcarin- 

 ated, 8-valved, the intermediate valves wider than the others, having 

 the summit somewhat beaked, and the lateral areas separated from 

 the median by a projecting rib. Anterior valve small, semicir- 



