TONICIA. 211 



central areas, and the development of angular scattered pits there. 

 The tail-valve is emarginate behind as in Eudoxochiton and many 

 Tonicias. Fig. 33 represents the interior of the second valve, which 

 is longer than the following valves, as usual in Tonieia. 



It is not easy to see how Gould could write so confidently of the 

 plurality of side slits, unless he examined the figures in the Explor- 

 ing Expedition Atlas instead of the specimen itself; but this is no 

 doubt the case. The artist of the expedition in drawing these figures, 

 mistook the deep pectination for veritable slits, and represented them 

 as such. In the figured specimen, now before me, the girdle in dry- 

 ing has parted from the eaves, partially exposing the deeply pectin- 

 ated insertion-plates, as represented in figures 434 b of the Atlas ; 

 but as I have above explained, the deeper grooves of the pectination 

 have been very erroneously drawn in those figures as slits. The fact 

 is that although the grooves are strong and deep on the outside of 

 the plates, they scarcely crenulate the summits of the teeth, and are 

 as different as possible from true slits. 



The genus or subgenus Lucia (Lueilind) has therefore no stand- 

 ing whatever, but becomes a synonym of Tonicia. This species can- 

 not be included in Acanthopleura on account of the different arrange- 

 ment of the eyes, the smooth girdle (which in this species seems to 

 be more fleshy than leathery), and the denticulate sinus. 



T. PICTA Keeve. PI. 40, figs. 5, 6. 



Shell ovate ; valves, the posterior terminal truncated, ornamented 

 with short, sharply undulated wrinkles, the interstices between which 

 are punctured ; anterior edge of the lateral areas keeled ; pinkish- 

 white, showily painted with green and scarlet spots. Ligament 

 horny, transparent. (Jffoe.) 



Raine's Island, Torres Sts. (Capt. Ince.) 



C. pictus REEVE, Conch. Icon., t. 15, f. 79 (March, 1847.) 

 Allied to C. truncatus, distinguished by its sculpture and flattened 

 growth. (Rve.~) 



T. TRUNCATA Sowerby. PI. 40, figs. 1, 2. 



Shell oblong, rather elevated, the dorsal ridge rounded ; ashy- 

 flesh colored, variegated with darker or olivaceous, dotted with 

 black, and sometimes rose-tinted along the dorsal ridge. 



Valves much rounded and separated at the ends ; entire surface 

 granulose ; central areas engraved with superficial waved grooves ; 



