Prof. E. Forbes on Fossil Invertebrata from Southern India. 105 



Diameter . • Oy^^ inch. 



Diameter of outer whorl Oy^jj inch. 



Thickness Oy'^^ inch. 



Shell resembling a flattened species of Planorbis, the outer whorl dorsally com- 

 pressed so as to exhibit a slight tendency to carination ; the inner whorls ex- 

 posed, 4 or 4^, their inner margin sudden and steep. Umbilicus shallow. Cham- 

 bers apparently rather simple ; lobes about four, the dorsal nearly equalling the 

 superior lateral, which appears to be trifurcated, and not so broad as the former. 



Locality, Pondicherry. 



Heterophylli. 



11. Ammonites Indra, sp. nov. PI. XI. fig. 7. 



A. testa inflata, umbilicata, striata, laevig-ata, anfractibus amplexantibus, dorso rotundato 

 apertura dilatata, ovata. 



Median diameter . . . . . . . . 3y'^ inches. 



Oral diameter 4-^^ inches. 



Diameter of outer whorl ly*^ inch. 



Thickness ly^ inch. 



Shell resembling an umbilicated Nautilus, much-dilated at the mouth, where the 

 outer whorl becomes also somewhat elongated. Surface minutely striated, though 

 at first glance appearing smooth and polished. The umbiUcus is small ; in the 

 specimens examined it was hidden by rock. The umbilical side of the outer whorl 

 is rounded and sloping. The sutures are beautifully complicated. The lateral 

 lobes are four or five, gradually diminishing : they are trifurcated and much-divided, 

 springing from very narrow bases. The superior lateral is much the largest, and 

 slightly exceeds the very large, much-ramified and deeply bifurcated dorsal. The 

 saddles are bifurcated, their extreme divisions more or less phylliform : the supe- 

 rior lateral saddle is largest. The partitions are arranged obliquely, and their 

 sutures encroach nearly on each other. 



A very distinct and beautiful species, one of the finest in its section. 



Locality, Pondicherry. 



12. Ammonites diphylloides, sp. nov. PI. VIII. fig. 8. 



A. testa compressa, laevigata ; umbilico leviter impresso ; anfractibus amplexantibus latera- 

 liter depressis ; dorso rotundato ; apertura ovato-lunata. 



Diameter Oy% inch. 



Diameter of body-whorl ..... Oy*o inch. 

 Thickness Oy% inch. 



Resembling A. Rouyanus in form, but compressed and not dilated at the mouth. 



