696 report— 1884. 



Before proceeding with the argument it is as well to call attention to the very 

 important fact just mentioned. It has been asserted over and over again that 

 species of mammalia are peculiarly short-lived, far more so than those of mottusca. 

 In this case, so far as the evidence extends at present, one-third of the species 

 of mammalia survived the changes that took place, whereas not a single mollusk 

 is found both in the upper and lower Siwaliks. It should be remembered that 

 the recent molluscan river fauna of this part of India is very poor in species, 

 and that we probably know a considerable proportion of that existing in Siwalik 

 times. 



The geological age of the lower Siwalik beds of Sind is shown by their passing 

 downwards into marine fossiliferous beds, known as the Gaj group, of Miocene 

 age, the following being the section of Tertiary strata exposed in the hills west of 

 the Indus : — 



Ft. 



["Upper . 5,000 unfossiliferous . . . Pliocene 

 Siwalik or Manchar- Lower . 3,000 to 5,000 fossiliferous . Upper Miocene or 



L Lower Pliocene 



Gaj 1,000 to], 500 fossiliferous . Miocene 



jj- ari / Upper . 4,000 to 6,000 unfossiliferous. Lower Miocene 

 I. Lower . 100 to 1,500 fossiliferous . Oligocene 



Khirthar . . . ./Upper . 500 to 3,000 fossiliferous O 

 1_ Lower . 6,000 fossiliferous . . . J 



Eocene 



Clearly the lower Siwaliks of Sind cannot be older than Upper Miocene ; there- 

 fore the Upper Siwaliks, which are shown by both biological and geological 

 evidence to be of much later date, must be Pliocene. 



Gondwana System of India. — In the peninsula of India there is a remarkable 

 deficiency of marine formations. Except in the neighbourhood of the coast or 

 of the Indus valley there is, with one exception (some cretaceous rocks in the 

 Nerbudda valley), not a single marine deposit known south of the great Gangetie 

 plain. But iu Bengal and Central India, over extensive tracts of country, a great 

 sequence of fresh-water beds, probably of fluviatile origin, is found, to which the 

 name of Gondwana System has been applied. The uppermost beds of this system, 

 in Cutch to the westward, and near the mouth of the Godavari to the eastward,, 

 are interstratified with marine beds containing fossils of the highest Jurassic 

 (Portland ian and Tithonian) types. 



_ The Gondwana system is a true system in the sense that all the series com- 

 prised are closely connected with each other by both biological and physical 

 characters, but it represents in all probability a much longer period of geological 

 time than do any of the typical European systems. The highest members, as 

 already stated, are interstratified with marine beds containing uppermost Jurassie 

 fossils. The age of the lowest members is less definitely determined, and has 

 been by different writers classed in various series from Middle Carboniferous to 

 Middle Jurassic. The Gondwana beds from top to bottom are of unusual interest 

 on account of the extraordinary conflict of palreontological evidence that they 

 present. 



The subdivisions of the Gondwana system are numerous, and in the upper 

 portions especially the series and stages are different in almost every tract where 

 the rocks are found. The following are the subdivisions of most importance on 

 account of their fauna and flora, or of their geological relations : — 



f Cutch and Jabalpur 

 Upper Gondwana . . . . 1 Kota-Maleri 



(.Rajmahal 



rPanchet 



n,,™,,,^ fRanigani and Kamthi 



Lower Gondwana .... J Damuda . . . . j Bara f ar J 



/"Karharbari 

 I (Talchir 



