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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Mar. 20, 



degree probable tbat the generic forms of Ferns may have had a 

 wide range in time also, and that allied (though not identical) species 

 may have existed in very different ages. I do not wish to lay much 

 stress on this argument ; but it may suggest a certain degree of 

 caution. The genus PhyUotheca affords more decided evidence of 

 Jurassic affinities in the fossil flora of the Indian and Australian 

 coal-fields, since the only known species out of those coal-fields 

 have been discovered by M. de Zigno in an undoubtedly Jurassic 

 formation in Northern Italy*. The other vegetable remains of the 

 deposit we are considering are too uncertain in their nature and 

 affinities, or too remote from any known in Europe, to afford any 

 help towards determining the question of age. 



On the other hand, there is in the Nagpur collection a striking 

 deficiency of the Cycadece (PterojphyUum, Zamites, Otozamites, and 

 the like), a family very characteristic of the Jurassic flora in Europe. 

 This deficiencj'does not extend to the plant- bearing deposits of Bengal. 

 Dr. McClelland describes several well-marked Cycadece, from the 

 liurdwan coal-fields. In a set of drawings, which I have examined, 

 of fossil plants procured by Prof. Oldliam from the Eajmahal Hills, 

 as many as nine out of thirteen forms represented are undoubted and 

 well-characterized Cycads. In the Australian coal-fields, again, I 

 have no evidence that any Cycads have been found. The question 

 may therefore arise, are the fossil plants of JNagpur contemporaneous 

 with those of Australia, and of a different age from the Burdwan 

 and Bajmahal deposits '? But the Glossopteris Broivniana appears to 

 be common to the Australian and Bengal coal-fields f ; so also is the 

 very peculiar and characteristic form called Vertebraria. I think, 

 therefore, that the several plant-bearing deposits of which I have 

 been speaking, cannot well be separated geologically, and that, as 

 far as the evidence derived from fossil plants can be trusted %, there is 

 a strong probability that they arc all of Jurassic, or at least of Meso- 

 zoic age. 



4. The fossil flora described in this paper appears fully as differ- 

 ent from the existing vegetation of India, as the fossil flora of our 

 Jurassic or our Carboniferous rocks is from the existing vegetation 

 of Europe. Drs. Hooker and Thomson, in their admirable Intro- 

 duction to the 'Flora Indica,' have shown us what are the character- 

 istic families, genera, and species of plants in the different districts 

 of India; and in none of these districts do we find anything 

 resembling the fossil vegetation of Nagpur. The predominance of 

 Ferns, the absence of any certain indication of ordinary (angio- 

 spermous) Exogens, the absence of Palms, and, in fact, the apparent 

 absence of all those families and genera of plants which can be 

 considered in any way characteristic of the Indian flora, strikingly 

 distinguish this extinct vegetation from that of the present day. If 

 it were contemporaneous with our Jurassic flora, it cannot be denied 



* De Zigno, Fl. Foss. Form. Ool., pp. 59, 60. 



t Brongniart, Hist. Yog. Foss. ; McCoy ; Morris in Strzelecki's New South Wales. 

 \ To what extent evidence of this sort can be trusted must remain doubtful 

 until the Tetit-Coiur mystery shall be solved. 



