OF SOUTHERN INDIA. 357 



only a slight indication of the usual pedal and byssal gape of Barhatia ; the liga- 

 mental area is very narrow, the hinge line straight, but the hinge-teeth have not 

 been made visible, the valves being closed. 



Locality, — Ninnyoor, va. a whitish sandy limestone. 



i^(9rma^^6>^.— Arrialoor group. 



2. Baebatia diatreta, StoliczJm, PL L, Fig. 9. 



Barb, testa elongate ovata, valde incBquilaterali, modice inflata, antice breviori, 

 angustata, infra conspicuiter insinuata ac hianti, postice producta, multo latiore, 

 ad marginem oblique sub-rotundata ; area mediocri, angulatim striata ; umbonibus 

 approximatis, depressiusculis, sub-sulcatis ; superficie radiatim striata, striis alteris 

 Goncentricis incrementi ad intervalla interruptis. 



Height of shell : its length ... ... ... ... 0*56 



Thickness „ : „ ... ... .,. .., 0*45 



A typical form of a Barbatia and closely allied to several recent species, 

 particularly some of the varieties of velata, with the anterior side of the shell 

 considerably narrow. The flattened slightly sulcated beaks and the posterior 

 broadly rounded shell distinguish this species, though the single specimen is not 

 in very good state of preservation. 



Locality, — South-east of Veraghoor, in a brownish finely oolitic rock. 



Formation. — Trichinopoly group. 



AROA, Linne, 1799, (see p. 34il). 



1. Arca pilistriata, Stoliczka, PL XVII, Pig. 37, PL L, Pig. 6. 



A, testa elongata^ inflata, antice levissime flexuose sub-truncata^ infra profunde 

 insinuata, postice latiuscule et convexe sub-truncata, ab umbone sub-carinata, declim- 

 tate Gosta longitudinali divisa ; sttperficie radiatim filiforme striata, striis lamellis 

 incrementi crassiusculis interruptis ; area ligamentali longitudine testcBfere cequante, 

 latissima, angulatim striato-sulcata, umbonibus distantibus. 



Approximate height of shell at the beaks : its length ... ... 0*45 



„ thickness „ : „ ... ... 0"42 



This is the only species of Area (as restricted) found in the South Indian 

 cretaceous rocks, and the single specimen is somewhat imperfect, but it sufficiently 

 exhibits the characters of the genus. The striation is very similar to that of the 

 last mentioned species of Barbatia, but the striae are more distinctly filiform, and 

 the lamellae of growth much more strongly developed. 



Locality, — North of Odium, in a brownish limestone ; very rare. 



Formation, — Ootatoor group. 



