184 fissukellidjE. 



Species of Fissurella. 

 Sect. I. Shells with distinct internal marginal border. 



1. nigra (f. 14), Lesson. — Testa magna, elevata, ovali, ni- 

 grescente, sublsevigata, striis evanidis radiata, foramine albo, mar- 

 ginata, subcentrali, antice depressa, intus alba ; margine cseruleo, 

 subcrenulato, ad apicem callo iuterno late erenulato. Obs. A 

 broad, smooth, nearly oval species, of a dark inky colour. 



2. limbata (f. 23, 24), Soivb. — Ovali, conica, antice vix at- 

 tenuate, lsevi, radiis rubris vel spadiceis latis radiata ; aperturae 

 margine intus violaceo ; foramine oblongo, subcentrali, intiis vix 

 calloso. Obs. Not so elevated as the preceding, and very brightly 

 rayed with purple bands. 



3. Bridgesii (f. 21, 22, 34), Reeve. — Crassa, depressa, ob- 

 onga, sublaevigatii fulvo-grisescente, antice attenuate, intus alba ; 



margine lato, purpureo, lcevi ; foramine ovali paululum infra 

 medium posito, marginibus elevatis, intus calloso. Obs. Kather 

 flat, attenuated in front, and of a greyish-brown colour. A very 

 curious specimen in Mr. Cuming's collection is represented (f. 22), 

 in which the foramen has been completely filled up with callus, 

 which usually surrounds it. The same phenomenon has very nearly 

 occurred with the specimen of F. maxima represented at f. 9. In 

 both cases, the anal tube must have been bent round so as to pass 

 under the side of the basal aperture. F. 34 is a narrower variety. 



4. fdlvescens (f. 36), Sowb. — F. Bridgesii simili, sed flavida, 

 rubro radiata ; terminibus paululum elevatis. Obs. Very like the 

 preceding, but yellow, with purplish-red rays, and the ends a 

 little elevated. 



5. grisea (f. 85), L'eeve. — F. Bridgesii simili, sed magis 

 ovali et elevata ; foramine magis centrali. Obs. This may be an 

 abnormal form of Bridgesii, more oval and elevated, with the 

 foramen more central. 



6. crassa (f. 10, 17), Lamb. — Oblonga, crassa, depressa, oli- 

 vaceo-fulva, obscure radiata, laevigata concenlrice et ad marginem 

 undulata; intus callosa, radiatim rugata ; area mediana rosea; 

 foramine elongato, in medium contracto, intus valide calloso. 

 Obs. A peculiarly flattened oblong species, thickened within. 



7. PULCHiiA (f. 31), Soicb. — Ovali, lasvi, depressa, antice 

 paululum attenuata, fulvo-grisescente, prope medium fasciis ra- 

 diata et maculis rubris nigris et albis variegata ; foramine sub- 

 centrali, oblongo medio contracto. Obs. Shorter than F. Bridgesii, 

 with delicately variegated rays. 



