FissoREixuxa;. 197 



nato, antice angustato, supra medium posito. Obs. Of an oblong 

 depressed form, with eighteen imbricated rounded ribs, and three 

 smaller ones in the interstices. The fissure is singularly nar- 

 rowed anteriorly. 



88. Dysoni (f. 105, 10G), Rve. — F. larva simili, sed magis 

 conica ; costis magis angulatis, acute imbricatis. Obs. More coni- 

 cal than F. larva, with the ribs and imbrications more angular. 



89. fumata (f. 95, 96, 97), Rve. — Ovali, conica, antice an- 

 gustata, alba vel griseo-nebulosa, post foramen angulatim elevata, 

 concentrice lirata; costellis rotundis crebris, quarum IS majori- 

 bus radiatis ; foramine declinato, antice angustato, creruleo mar- 

 ginato, ante medium posito. Obs. The variety figured in Reeve's 

 work appears to be an unusual one; the smoky tints of our figures 

 are more natural to it. The apex is elevated into a point behind 

 the anteriorly-narrowed fissure. 



90. alterxata (f. 9S, 99), Sai/. — Oblonga, quam F. fumata 

 magis angusta, fusco-subviridi fasciutim variegata; costis majoribus 

 acute imbricatis. Obs. Narrower than F. fumata, with the more 

 prominent ribs sharply imbricated, and the colouring variegated. 



91. Rupellii (f. 107, 10S), Sowb. — Ovali, antice subincurva, 

 postice convexa, alba, fasciis quatuor vel octo nigrescentibus, vel 

 fulva vel prope marginem rufescente-nigro radiata, costis validis 

 rotundis moniliferis et liris coucentricis parvis cancellata ; intus 

 albo, margine minute denticulato ; foramine declivi, ovali, sim- 

 plice, supra medium posito. Obs. The rounded and beaded large 

 ribs distinguish this species from others. 



92. Ticaonica (f. 110), Rve. — Oblonga, postice gibbosa, an- 

 tice valde declinata, concentrice leviter lirata, costis scabris radiata, 

 alba viridi tincta, nonnunquam viridi interruptim radiata; fora- 

 mine angustato, tripartite, prope marginem anticum posito. Obs. 

 The tripartite fissure, the fine and rather sharp cancellation, and 

 the nearness of the apex to the ventral margin, serve to distinguish 

 this species. 



93. proxima (f. 115), Sowb. G. B. 2.—F. T/.caonica simili, 

 sed postice baud tantum gibbosa, antice haud bantam declinata. 

 Obs. Less gibbous posteriorly and less suddenly inclined than 

 /■'. Ticaonica, which it nearly resembles. The variety figured is 

 marked by green lines. 



94. Cayennensis (f. 101), Lamk. — Ovali, postice arcuata, 

 antice declivi, costellis scabris crebris radiata, fusca, nigro et albo 

 variegata; intus albo, callo nigro-marginato, truncato, margine 



vol. in. i A 



