194 



pronounce it a Helix. But its small number of whorls, and the 

 statement of Dr. Perkins that the animal is very large and slug- 

 gish, so that it cannot retract within the shell, would bring it 

 more properly within this genus. The sculpture of its upper 

 and lower faces distinguishes it. 



Helix indecorata. T. parva, tenui,orbiculato-depressa, arete 

 umbilicata, nitida, glabra, virescente ; spira depresso-convexa, 

 anfr. 5^ convexiusculis, ad suturam bene impressam marginatis ; 

 subtus convexa ; apertura lunata, labro acuto. Diam. f , alt. :|- 

 poll. Hob. Liberia. 



A very plain species, resembling in form small specimens of 

 H. ligera ; but in the characters of surface and umbilication it is 

 more like a diminutive H. inornata. The whorls revolve more 

 closely in the same space, and form a more dome-shaped spire 

 than the incipient whorls of H, pellucida. 



Helix cerea. T. parvula, vix perforata, fragili, depresso- 

 orbiculari, lucida, nitida, albido-straminea ; spira depresso-conica, 

 anfr. 5 convexiusculis ad suturam marginatis ; apertura lunata ; 

 labro acuto. DIam. ^ ; alt. ^ poll. Hab. Cape Palmas. 



Very similar in its characters to the preceding, but is less than 

 half its size, of a very different color, and the umbilical region 

 differs considerably, especially the reflection of the lip at that 

 part, which does not cover the portion of the umbilicus next the 

 aperture, but turns round at right angles to it. It may be 

 compared to H. alliaria, but the umbilic is not half as large. 

 The animal is glossy black and extremely active. 



Helix talcosa. T. parva, tenui, vix perforata, pyramidali, 

 talcosa, spiraliter acutissime lirata, basi glabra ; spira conica, 

 anfr. 7 planis, ultimo acutissime carinato ; apertura rhomboideo- 

 lunata. Diam. f ; axis f . Hab. Cape Palmas, on bark of trees 

 in forests. 



Remarkable for its trochoid form and silvery lustre, on ac- 

 count of which it would most likely be pronounced a marine 

 species. H. Ibuensis accords well with this, excepting that the 

 sharp revolving lines, about three or four on each whorl, are not 

 mentioned. 



BuLiMUs MuciDUS. T. solidula, ovata, mamillata, indentata, 

 granuloso-striata, flavida, longitrorsum strigis interruptis nigris 



