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



of all the others. As the contiguous chambers encroach on each other at the 

 sutures, great complexity is given to the pattern they describe. 



The oolitic Ammonites discus (Sowerby), the Neocomian A. clypeiformis (D'Or- 

 bigny), and the A. Requienianus (D'Orbigny) of the French ' craie chloritee' are all 

 very near allies of this fine species from Pondicherry. 



Armati. 



22. Ammonites Menu, sp. nov. PI. X. fig. 1 . 



A. testa discoidea, inflata, obsolete undulata, striata sulcataque, sulcis transversis distantibus 

 marginatis ; dorso lato, subquadrato^ lateraliter tuberculato ; umbilico impresso ; apertur^ 

 lata (lunato-quadrata?). 



Diameter 2-^-^ inches. 



Diameter of outer whorl IjL inch. 



Median thickness ly'^ inch. 



Shell suborbicular, much inflated, smooth or minutely striated, the outer whorls 

 with two series of tubercles, those most dorsal larger than the inner, which have a 

 tendency to be prolonged superiorly into ribs. The back is slightly rounded and 

 free from ribs, but rendered somewhat quadrate by the bordering tubercles. An- 

 teriorly there are two deep sulcations with raised borders, crossing the shell and 

 continuous round the outer whorl. The mouth, which is broken away, appears 

 from the section to have been broad, lunate and somewhat quadrangular, owing to 

 the projecting tubercles. In the young shell the dorsal series of tubercles appears 

 to be wanting. 



The chambers are extremely complicated. The lateral lobes are three, of which 

 the superior lateral is much the largest ; they are trifurcated and much pinnate. 

 The dorsal lobe is not quite so long as the superior lateral ; it is much divided at the 

 sides and separated at the extremity by a short, square, dentated, siphonal saddle. 

 The saddles are as much divided as the lobes and are unequally bifurcated, the 

 furcations deeply crenate and much divided. The nearest allies of this species 

 are oolitic, to which formation all the European species of the division belong. 



Locality, Pondicherry. 



LcEvigati. 



I propose to establish a distinct section, under the above name, for Ammonites 

 which have smooth, ribless, compressed sides, and the back encircled by a sipho- 

 niferous keel, 



23. Ammonites Rembda, sp. nov, PL VII. fig. 3. 



A. testa compress^, laevigata; late umbilicata; dorso carinato; carina simplici, fiUformi, 



q2 



