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



Resembling many known forms, both cretaceous, tertiary, and recent, but appa- 

 rently sufficiently distinct from all. 

 Locality, Pondicherry. 



[Section B. Modiolus auctorum.] 



2. Mytilus {Modiolus) cypris, sp. nov. PI, XVI. fig. 7. 



M. testa oblonga, depressa, laevi, marginibus parallelis, umbonibus subterminalibus, extre- 

 mitatibus rotundatis. 



Length from beak to extreme margin 0^-^ inch. Breadth across the centre 0^ j inch. 



Locality, Pondicherry. Specimen bad. 



3. Mytilus (Modiolus) typicus, sp. nov, PL XIV. fig. 4. 



M. testa cuneato-oblonga, convexa, dorso tumido, margine frontaU expanso transverse 

 striato-costato, striis in latere cardinah fortioribus, elevatis, plerumque in medio bifurcatis, 

 fasciculo obliquo striarum longitudinaHum in centro dorsi decussatis. 



Length from beak to margin 4 inches. Greatest breadth 1| inch. 



A very remarkable form, combining the characters of several sections of this 

 variable genus. The beaks are placed at the shortest end, very near it. and from 

 them runs diagonally a tumid dorsal convexity to the anterior margin of the dilated 

 opposite extremity. The dorsal margin is nearly straight, and angulated ante- 

 riorly. The dorsal side of the central ridge is marked by bifurcating striae and the 

 ridge itself by a bundle of fine oblique striae marking its course. The space in 

 front of the central ridge is nearly smooth. 



Locality, Verdachellum. 



4. Mytilus (Modiolus) flag elliferus, sp. nov. PI. XVI. fig. 9. 



M. testa elongata, lanceolata, subarcuata, antice dilatata, diagonaliter bipartita, divisione 

 dorsali costis arcuatis flagellatis, ventrali tevigato, umbonibus obtusis, terminaUbus. 



Length from beak to farthest margin 4| inches. Greatest breadth at dilated end 1 inch. 

 Median breadth OJ inch. Greatest thickness, valves united, Ojg inch. 



This species is remarkably razor-shaped, with very terminal beaks. The hinder 

 half of the surface, which is divided into two parts by a diagonal obtuse ridge, is 

 marked by curved ridges or ribs, which on the back are trifurcated, like a whip of 

 three thongs. The front division is smooth, or marked by furrows of growth. The 

 young shell is marked with obsolete longitudinal striae. This species is nearly 

 allied to the Modiola plicata of the Cornbrash, but in the latter the plications 

 divide into twenty or even more thongs. 



Locality, Pondicherry. 



