1S76.] Knowledge of the Fossil Flora in India. 341 



form either a dentate upright spathe or an oblong-oval leaf, which, however, 

 would also be upright in the manner seen in Fquisetum and Schizoneura. 

 In the latter genus there are generally two spathe-portions, which are 

 oblong-oval and contain as many distinct simple veins as leaflets have 

 grown together ; in some cases we see the leaflets separated again by 

 dehiscence, but they could never produce anything like the leaf of 

 Sphenophyllum, in which also the forked veins afford a chief difference. 



I am much inclined to believe that both genera have the same micro- 

 scopical structure and belong to the same order ; but I think it is against all 

 morphological and biological laws to suppose that linear leaflets, which 

 are attenuated at both ends and all contain invariably only one undivided 

 rib, could ever by their coalescence produce a wedge-shaped leaf, with a 

 narrow base and a disproportionally broader apex, and with 2 or 3 chief 

 veins, which are repeatedly forked to the margin. 



All these relations, together with the much thinner stalks and a differ- 

 ent fruit-spike, will, as I think, still maintain SpTienopliyllum as a peculiar 

 genus belonging, with Aster opliyllites, to the same order ; but that this 

 is that of the Lycopodiaceae, must, as I think, be thoroughly proved* 

 before one can draw any conclusions. 



But for the present I think it is better to leave them both in the 

 class Fquisetaceae, when following Schimper's system, we have : — 



Class : EQUISETACEAE.f 



Order I. — Equiseteae, true horsetails. 

 E q u i s e t e u on, Linn. % 

 S c h i z o n e u r a, Schmp. § 

 Fquisetides, Schmp. 

 Phyllotheca, Bgt. || 

 Order II. — Calamaeieae. 

 Calamites, Suits. 

 Asterophpllites, Bgt.^1" 

 Fruit-spikes. 



Sp henophyllu m, Bgt. 

 Annularia, Bgt. 

 Schimper does not mention the Sphenopliylhom from our Damiidas 

 at all ; and his diagnosis, therefore, as referring only to the palaeozoic 



* While this paper is passing through the press, I have heard that Mr. Stur of 

 Vienna proves that Sphenophyllum cannot by any possibility be a Lycopod. 

 f The Indian forms are spaced. 



X None in Danmdas ; one species in the Rajmahal Hills. 

 § Very abundant in the Eaniganj group and in Trias in Exuope. 

 || Very frequent also in Italian Oolite. 

 H Schimper uses Calamocladus, Schirnp. 



