122 Prof. E. Forbes on Fossil Invertehrata from Southern India. 



doubtless produced by the spiral grooves crossing the extremities of the oblique 

 sulcations and their intermediate ridges. The pillar-lip is broad and smooth. In 

 most of the specimens it is concealed by rock, so that the shell presents the aspect 

 of a Neritopsis. 



Locality, Pondicherry, where it appears to be common. 



2. Nerita munita, sp. nov. PI. XII. fig. 15. 



N. testa late ovata, depressa, spira parva exsertiuscula : anfractibus 4 laevibus, ad suturam 

 late sulcatis, sulco piano, forte marginato ; aperturfi semilunari. 

 Length li inch. Breadth Off inch. 



An ovate smooth shell, with a very small and low spire. The whorls are cari- 

 nated near the suture by a fold which runs along the spire like a little wall. The 

 space between this fold and the suture is fiat, not excavated. The characters of 

 the pillar-lip are concealed by rock. It is a very distinct species, and cannot be 

 compared with any fossil with which I am acquainted. 



Locality, Pondicherry. 



3. Nsrita oviformis, sp. nov. PI. XII. fig. 13, 



N. testa ovat&, globulosa, inflate ; spir^ brevi, obtusissima ; anfractibus 3 Iccvibus ; aperture 

 ovato-pyriformi. 



Length l^'^ inch. Breadth 0~ inch. 



A smooth egg-shaped shell with a very obtuse spire, the distinction between the 

 whorls marked only by the suture. The characters of the pillar-lip are concealed 

 by rock. It is as distinct from described fossil forms as the last species. 



Locality, Pondicherry. 



4. Nerita compacta, sp. nov. PI. XV. fig. 6. 



N. testa ovata, subglobosa, laevigata (sub lente minutissime striata), spira minute, obtusissim^ ; 

 sutura impressa ; anfractibus tribus ; apertura lunato-truncata, labro columellari incrassato. 

 Length 0| inch. Breadth 0^^^ inch. 



This beautiful and curious little Nerita resembles remarkably some of the 

 varieties of the living Littorina neritoides. It is ovato-globose, with a very small 

 and obtuse spire of three whorls, indicated only by the deeply impressed suture. 

 To the eye the surface is smooth, but the lens shows a double striation, consisting 

 of — 1st, well-marked regular equidistant lines of growth, and, 2nd, very minute 

 radiating strise, as if the remains of a glistening epidermis. The mouth is lunate, 

 and truncated by the thickened pillar-lip. Its nearest ally is the species last 

 described. 



Locality, Trinchinopoly. 



