Prof. E. Forbes on Fossil Invertebrata from Southern India. 115 



The chambers are beautifully marked. There are five lobes and five saddles, 

 all symmetrical. The dorsal lobe is very wide, and its two crenated branches are 

 separated far apart by a wide siphonal saddle. The superior lateral lobe is longer 

 than the dorsal, but not so broad ; the inferior laterals are wider than the superior, 

 but not so long. The lateral saddle is longer and broader than the dorsal ; the 

 saddles are elegantly, though not deeply, crenate, and the lobes similarly dentate. 

 The ventral lobule is very short, ovate, crenate and unsymmetrical at its extre- 

 mity. 



Locality, Pondicherry. Apparently abundant. Nearly allied to Baculites incur- 

 vatus of Dujardin, and to the Baculites anceps of Lamarck. The form and the 

 more transverse tubercles distinguish it from the former ; the tubercles and the 

 conformation of the chambers from the latter. 



2. Baculites teres, sp. nov. PI. X. fig. 5. 



B. testa tereti, undique rotundata; laevigata, leviter undulata, striis longitudinalibus obsoletis, 

 apertura obliqua, sinuata. 



Length (of largest fragment) .... 2 inches. 

 Maximum breadth Oi inch. 



Shell completely cylindrical, gently tapering, marked with obsolete regular 

 longitudinal striae, which are not always clearly visible, and obscure undulating 

 oblique transverse folds. The chambers are not visible in the specimens examined. 

 This remarkable and very distinct Baculite appears to be the analogue of the B. 

 neocomiensis of D'Orbigny. 



Locality, Pondicherry. 



Genus Turrilites, Lamarck. 



To this genus probably belongs a Planorbis-like cast of four contiguous whorls, 

 which are convex, rounded, and obscurely undulated : the aperture is round. I 

 have named it provisionally Turrilites planorbis. It measures i^ths of an inch across, 

 and the last whorl is ifjths of an inch thick. PI. IX. fig. 5. 



Genus Hamites, Parkinson. 



The Hamites in this collection appear all to belong to a group having widely- 

 apart spiral terminal volutions, a character of the genus Ancyloceras of D'Orbigny. 

 But all M. D'Orbigny's species of Ancyloceras have the lobes of their chamber^ 

 partitions divided into " parties impaires," whereas all the Pondicherry species 

 have their lobes as in Hamites, divided into " parties paires," i. e. bifurcated 

 instead of trifurcated. I regard Ancyloceras, however, as only a section, and 

 scarcely even that, of Hamites, to which Crioceras, or at least a part of that genus*; 

 * See Morris on the genus Ancyloceras in Annals of Nat. Hist. vol. xv. p. 30. 



