422 CRETACEOUS PELECYPODA 



obliqiTcly dcsccndiug ; the ligamental pit lies below tlie beak, somewhat posteriorly 

 from the centre. 



Localities. — Near Comarapolliam and north of An-ialoor, in coarse silicious 

 sandstone ; near Poodoopolliam, in white earthy limestone. 



Formation.— Axvhloov group. 



There are two species which deserve notice, as being closely allied to the Indian 

 species: E. Eaiiliniana and omata oi d'Orbigny; the former is from the Gault, 

 and differs only by a slightly more expanded posterior ear; the other is upper 

 cretaceous, and has the anterior side somewhat more incurved. A comparison of 

 well preserved specimens of these, and one or two closely allied species from 

 the German upper cretaceous beds, would be very desirable, as, for instance, 

 E. aspera, Miinst., particularly the form figured by Reuss from Bohemia. 



14. Radula [Acesta] scrobiculata, Stoliczka, PI. XXIX, Pig. 6. 



E. [^c] testa late semi-ovata, obliqtm, compressiiiscula, antice recte sub-truncata, 

 postice rotundata, atiriculis parvis, antica minima, lunula paulo excavata; superficie 

 striis vel costulis radiant ibus, stib-obsoletis, scobinatis, in parte antica magis distinctis, 

 notata. 



Shell rather broadly semiovate ; valves slightly convex, anteriorly trancate ; 

 ears small, the anterior scarcely visible in a side view ; lunula slightly excavated ; 

 surface marked with indistinct radiating scaly ribs, or rather striae, somewhat more 

 distinct on the anterior portion of the shell. Sometimes the scales wear ofi" on the 

 ribs altogether, while the cross lines connecting them, and situated in the furrows 

 between the ribs, partially remain preserved, and this gives the shell quite a dis- 

 tinct appearance from that it originally possessed. The largely ovate, almost 

 semicircular, and rather compressed shape of the valves readily distinguish the 

 present species from any other known from cretaceous rocks ; it in some respect 

 resembles the shape of Plagiostoma. 



Locality. — Near Olapaudy, in a brownish ferruginous rock. 



Formation. — Arrialoor group. 



15. Radtila [Ctenostreon] complanata, Stoliczka, PI. XXX, Pig. 14. 



E. \_Ctenost.'\ vulva sinistra elongata, deplanata, medio costis 10, radiantibiis, 

 crassis notata, antice et piostice Icevigata ; aiirictdis magnis, postica minore, antica, 

 majore, ad marginem inferiorem flateralemj simpUci, ad anticinn fsiiperioremj 

 paulo incrassata et in latere interiore sulco latiusculo insfructa. 



Only a single valve of this interesting species was found ; it belongs to the 

 sxib-genus Clenostreon, the larger anterior auricle being internally provided Avith 

 a shallow but distinct groove for the passage of the byssus ; at the margin itself 

 the groove is indicated by a very slight insinuation (which is scarcely sufficiently 

 indicated in fig. 14, pi. xxx) . The left valve is very slightly convex and marked 



