48 



s 



leviter striata, castaneo-fusca, subtus interdum lineolis flexuosis 

 nigris picta ; spira vix exserta, ultimo anfractu recurrente fere 

 involuta : apertura oblique semicircularis, magna, postice canali- 

 culata ; labro flavo ; labio planulato extrinsecus sanguineo tincto ; 

 columella alba, valde sinuata, denticulata. Operculum tenue, 

 lividum, sulco divisum, granulatum, ad apicem flavidum. Diam. 

 f- poll. Hab. Feejee Islands. 



Allied to the dark varieties of M. dubia, but distinct by its in- 

 volved and girded spire, like N. Bruguieri, and also by its very 

 sinuous and strongly-toothed pillar lip. It has a channel towards 

 the spire much like N. canalis, whose color and marking of the 

 ventral face it also resembles. 



Neritina chrysocolla. Testa solida, oblique conico-globosa, 

 coracina, lineis exilibus obliquis flavidis flexuosis picta : spira 

 elevata, erosa ; anfr. 2-3 ventricosis, infra suturam aliquid con- 

 strictis ; apertura oblique semi-elliptica ; labro cceruleo, viridi 

 limbato ; labio convexo, luteo-virente ; columella sinuata, dentic- 

 ulata : operculum osseum, salmonaceum, costa bisectum. Long. 

 £ , lat. § , poll. Hab. Upolu. 



Of the same group as N. communis, lugubris and helvola, but 

 distinct by its green, blue-edged outer lip and yellowish green 

 pillar lip, as well as by its very delicate zigzag lines, scarcely 

 seen except on the ventral face. 



Neritina helvola. Testa solida, conico-globosa, polita, co- 

 loribus fuscis et cervinis plerumque fulgurantibus diversimode 

 picta : spira prominula, erosa, anfr. 2 superstitibus : apertura 

 oblique semicircularis, helvola ; columella convexiuscula, callo 

 copioso induta, acute denticulata. Long. f-, lat. ■§ poll. Hab. 

 Feejee Islands. 



Closely allied toN. communis, but is rather more globular, and 

 generally smaller, and the aperture has a more nearly circular 

 outline. It has less brilliant and defined coloring, and is always 

 to be distinguished by its eroded tip, and the bright carnelian 

 color of its inferior face. 



Neritina siderea. Testa parva, ovata-globosa, polita, nitida, 

 nigra, punctis sparsis albis notata : spira prominula, erosa ; 

 anfr. 2-3 ; sutura marginata : apertura semicircularis, intus coe- 

 rulescens ; labio piano, angusto, luteo ; columella acuta, vix 

 denticulata. Operculum fuscum. Diam. £ poll. Hab. Feejees. 



