190 fissueellidjE. 



radiata, pallide fulva alb;1 et rubra radiatim fasciata ; intus viridi ; 

 forainine paulo supra medium posito, subquadrato. Obs. Very 

 much depressed, with three front ribs largely developed. 



42. asperella (f. 56), Sowb. — F. rugosce simili, sed costis multo 

 magis depressis et minutis. Obs. In this species the three promi- 

 nent ribs are depressed, although shown prominently by being left 

 white. The shell is more finely striated. 



43. microtrema (f. 54, 55), Sowb. — Ovali, antice paulo at- 

 tenuate, subangulata, compressa, castaneo rubesceute vel olivacea, 

 costis minutis irregularibus scabris ; intus viridi; margine crenu- 

 lato ; forainine parvo, nigro-marginato, supra medium posito, intus 

 calloso ; callo albo, nigro-marginato. Obs. Like F. asperella, but 

 with the minute ribs imbricated ; inside green, foramen very small. 



44. Natalensis (f. 69), Krauss. — Ovali-oblonga, subelevata, 

 antice angustata, alba fusco-nigrescente variegata, costis rugosis in- 

 aequalibus rotuudis radiata; intus alba; foramine oblongo, magno, 

 tripartite Obs. Rather narrow in front, with irregular rounded 

 ribs ; a long, divided foramen. 



45. nubecula (f. 73). Linne. — Ovali, antice angustata et 

 magis quam postice elevata, alba, fusco-subviridi nubila, radiis 

 subviridibus griseo maculatis radiatim fasciata, costis subplanulatis 

 interstriatis radiata; intus albo-viridescente ; forainine oblongo, 

 medio paulum contracto. Obs. The specimen figured from Mr. 

 Cuming's collection agrees very well with the description in the 

 'Systema' with which it has been identified. It is more elevated than 

 the following, with a much more elongated foramen. 



46. rosea (f. 91, 92, 150), Lamk. — F. nubecula simili, sed 

 magis depressa, costis nonnullis exstantibus, rubro radiata et varie- 

 gata; intus viridi; foramine ovali, brevi. 



47. ostrina (f. 84), Eve. — Ovali depressa, purpurea, albo 

 prope apicem radiata, costellis parvis striatis depressis radiata; 

 intus viridi; foramine oblongo. Obs. This obscure little shell is 

 oval depressed, finely ribbed, green within. 



48. mutabilis (f. 70, 74, 79, 93), Sowb. — Ovali, antice an- 

 gustata, lateribus subcompresssis, grisea vel roseii, irregulariter 

 planulatim costata et striata, intus alba; callo interno circum- 

 scripta; foramine ovali, medio coarctato. Obs. The front of this 

 shell is narrowed by the compression of the sides ; its surface is 

 radiated by impressed strise dividing the flattened unequal ribs, 



