GENERA AND SPECIES. 



Cerithium. (CERITHIIDJE.) Plate xxiv. 



443. metula, f- in. white, mouth oblong, 18 to 20 whorls. 



444. reticulatum, % in. white, mouth triangular, 1510 16 whorls. 



445. perversum, % in. brown, sinistral. 



446. vulgatum, ij in. shell grey and chocolate, with spiral nodulose 



ribs, a prominent row of nodules on each 

 whorl. 



There are two varieties of 444 simplex, in which the ridges are marked with purplish 

 lines ; and lactescens, which is whitish. 



There is also a variety of 445 pallescens which is whitish* 



Chiton. (CHITONID. 



190. fascicularis, 



191. discrepans, 



192. Jianleyi, 



193. cancellatus, 



104. cinereus, 



195. fl#WS, 



.) Plate xvi. 

 fin 



girdle, broad, spinous, with whitish tufts, 

 beaks small. 



in. girdle broad, spinous, with greyish tufts, 

 beaks sharp and projecting. 



in. girdle narrow, spinous, without tufts, beaks 

 small and'pointed. 



in. girdle narrow, covered with granules, beaks 

 inconspicuous except on tail plate, colour 

 yellowish white. 



in. girdle narrow, covered with granules, beaks 

 small, colour pale yellow. 



in. girdle broad, beaded with granules, ridge 

 sharp and conspicuous, colour yellowish 

 white. 



196. marginatus, $ in. girdle covered with granules, ridge prominent, 



beaks strong and conspicuous. 



197. ruber, in. girdle broad, mealy, and covered with 



granules, ridge indistinct, beaks projecting, 

 colour brown, streaked with yellow. 



198. l&vis, J in. girdle broad, reticulated, and covered with 



scales. 



199. marmorens, i in. girdle broad, membranous, and covered with 



scales. 



200. scabridus, J in. girdle narrow, colour brown, with radiating 



granules. 



Of 190 there are two varieties attenuata, which is longer and narrower, and gracilis^ 

 which is also larger and has a membranous girdle. Of 194 there is a variety rissoi which 

 is pale yellow in colour, and of 197 there is also one variety oblonga which is longer and 

 more arched. There is but one variety of 198, it is smaller and more arched, and is known 

 as navicula. 



Circe. (YEN BRIDGE.) 

 113. minima, in. x 



Plate ix. 



in. shell with flat concentric ridges, and of 

 many colours. 



There is a variety triangulates in which the beaks are more prominent, and the 

 sides more acute. 



