or SOUTHERN INDIA. 45 



D'Orbigny's figure is probably a little too bigb, but there are specimens ia 

 oiu' collectioa which are alraost identical with it in form. The most important 

 variations are sufficiently illustrated on plate xvi. 



Localitij. — In dark brown sandy and cherty limestone ; north of Odium ; not 

 rare. 



Formation. — Ootatoor group. 



4. CoRBULA CANCELLiFERA, StoUczlca, PI. I, Fig. 17 ; PL XVI, Fio-. 2. 



C. valvula sinistra sttb-trianffttlari, antice suh-rotandata, ad marginem injlexa, 

 postice ancjustata ac acuminata, umbone sub-antico, mediocriter jirominente, obtuse, 

 antice versus incurvo, carina acuta ab eo ad terminationem x>osteriore7n rectiuscule 

 decurrente instructa ; superjlcie striis conceutricis distantioribus, acutis, ac alteris 

 radiantibus, mimitissimis ornata. 



Heijrlit of left valve : its length ... ... ... 0-67 



Probable thickness of the shell : „ ... ... ... 0'47 



The ornamentation of this species is very peculiar and distinct from that of 

 any other known cretaceous species ; it approaches, however, in this point as well 

 as in its form to some of the recent species, like C. tunicata, Hinds, and others. 

 The concentric strioe are distant and very sharp, and the radiating lines are very 

 fine and close together ; they are better visible in the grooves than on the striae 

 themselves ; the posterior carina is slightly curved, it is especially sharp and promi- 

 nent near the end; the margin of the shell is anteriorly strongly inflected, very 

 similar to that of C. exulans n. sp. ; the recent species rarely have this inflection 

 equally strong. 



Locality. — In bluish, compact calcareous sandstone near Garudamungalum, 

 in company with C. parsura, and a large number of little Cardudm, Vmnerid^, &c. 



Formation. — Trichinopoly group. 



5. CoBBULA EXULANS, Stoliczka, PL I, Figs. 16 and 18 ; PL XVI, Figs. 1 and 5, 



C. testa sub-trigona, alta, ci'assa, compressiuscula, fere oiqu Hater ali, antice sub- 

 rotundata, iwstice angustata et sub-acuta, concentrice striata; umbonibus adpressis, 

 obtusis, parum incttrvis ; carina ab umbonibus ad terminationem posteriorem decur^ 

 rente prope marginem sita, mediocriter prominente ; valvula dextra sinistra paulo 

 majori. 



Height of shell : its length ... ... ,.. ... 0-76 



Thickness „ : „ ... ... ... ... 0-52 



This is a peculiarly triangular, high, nearly equilateral thick shell, laterally 

 much compressed, rounded in front and rather acutely angular posteriorly ; the right 

 valve is somewhat larger than the left one, both being perfectly closed round their 

 margins and inflected towards each other; the entire surface is finely striated. 



M 



