PLATE XXXVII. 



Figs. 1 — 3. ExoGYRA HALiOTOiDEA, Sou'., p. 458 ; 1, a large specimen with only the inner 



layers of the shell preserved; 2, a smaller specimen with the ridge-like 

 elevation of the larger valve placed rather near the central line; 3, inner 

 view of a flat valve ; Ooiatoor, Oofatoor group. 



Figs. 4 — 9. VoLA QUiNQUECOSTATA, Soio., p. 437 ; 4, a specimen from Arrialoor, with four 



intermediate ribs throughout ; 5 and 7, are from Comarapblliam, with three 

 intermediate ribs in between the four median larger ribs, and with four inter- 

 mediate ribs at the sides ; 6, from near OJium, partially with three, partially 

 with four unequal intermediate ribs ; 8j from near Andoor ; in one place only 

 with two large intermediate ribs, in the middle with three imequal ones, at 

 the sides with four unequal ones ; 9, from CumarajioUiam with three inter- 

 mediate ribs ; 4, 5, 7, and 9, are from Arrialoor ; 8, from TricMuo^oly, and 

 6, from Ootatoor, the three localities representing the three groups into which 

 the South Indian cretaceous deposits have been divided. 



