HISLOP AND HUNTER NAGPUR. 361 



on their stems, when closely examined, protuberances of aerial roots, 

 similar to those so frequently observed on the Wild Date of India. 

 In the more shady valleys are leguminous and other plants, in great 

 variety and profusion ; and there may be seen occasionally climbing 

 by numerous tendrils over the bushes, a cucurbitaceous plant allied 

 to the Lyffa, its tender stalk weighed down by a ponderous and 

 probably 10-angled fruit. The Nipadites here and there fringes the 

 marshy shores ; and wherever the water is shallow there rise above it 

 the reedy peduncles of Aroid plants, terminated at one season of the 

 year by spikes of flowers, and at another either by long succulent 

 purple fruit, resembling mulberries, or by large pericarps, that without 

 minute examination might be mistaken for cones.] 



Age of the Freshwater Deposit. — It has already been shown by 

 my esteemed colleague, in his concluding observations on the tertiary 

 plants (see above), that the body of water in which the strata containing 

 the above-enumerated fossils were deposited must have been a lake. 

 I shall now inquire at what period that lake existed. The determina- 

 tion of this question is attended with peculiar difficulties. In a 

 temperate climate like Britain, the discovery of a large number of 

 organisms fitted for a tropical abode at once demonstrates that the 

 rock in which they occur cannot have been deposited subsequently to 

 a remote tertiary period. Here, however, where we have a tropical 

 heat at the present day, the evidence derived from such a source is 

 much more equivocal. 



Still I think there are sufficient dissimilarities between our recent 

 and fossil floras to prove the great antiquity of the latter. While 

 there is a general resemblance between the two, inasmuch as Hedy- 

 sarece. Cassia, Lvffa, and Nipa are comprehended in both, there 

 may be remarked on the other hand the total extinction of two 

 genera, if not an order of endogenous plants, that once flourished 

 luxuriantly here, — I refer to the mulberry-like and strobiliform fruits, 

 which, though formerly so abundant, have at present no representa- 

 tive either in India, or so far as I know, throughout the world. We 

 must therefore direct our thoughts to some period comparatively 

 remote, when there was a greater uniformity of temperature over all 

 parts of the earth. Of the more ancient tertiary floras, none corre- 

 sponds with ours so well as that of the London Clay of Sheppey and 

 Belgium. In both of these localities we find Nipadites, and in the 

 former also the Xylinosprionites and Tricarpellites of Bowerbank, 

 fruits apparently alhed to those found at Nagpur. 



Of all the animal remains we have collected, scarcely one seems to 

 be identical with forms now existing on the surface of the globe. 

 The nearest approximation to specific identity is in one of the Cyprides, 

 and in the minute discoid Valvata ; but whether the identity is com- 

 plete, I am not competent to say. Supposing, however, that it were 

 proved to be so, this fact would micrely show that of all the living 

 tribes inhabiting the waters, or the margin of our old-world lake, not 

 one has survived in India, except a single species of Cypris, for the 

 Valvata minuta is not now found here, nor indeed does any species 

 of that genus appear to occur throughout Asia. But with these most 



