126 Remarks on the Ancient Flora (yfthe Earth. 



dependent of the classes of Agamous and Cellular Cryptogamia, 

 which here seem to us inconclusive, M. Brongniart next, in the 

 first period, recognised only the presence of members of the class 

 of Vascular Cryptogamiaand of Mcniocotyledonia. He has there- 

 by, however, as appears, allowed it to escape his observation, 

 that two species of his genus Conites, (C. cernuvs and arma- 

 tuSy xxxix. t. 29. f 1, 2. and t. 46, f. 1,) had been before de- 

 scribed and delineated by Count Sternberg, as belonging to the 

 coal formation of Bohemia, whose cones appeared so distinct, 

 that we can scarcely doubt that they may be justly ranked in the 

 family of the Conifene or Cycadea. Three of the more per- 

 fectly organised classes of Brongniart have shown themselves al- 

 ready in the first period, though the last, as regards the amount of 

 the whole, forms but a very insignificant fraction- In the number, 

 however, of the classes that M. Brongniart ascribes to his third pe- 

 riod, we consider ourselves entitled, from the foregoing observa- 

 tions, to notice an exception. We here find the appearance of 

 Dicotyledones expressly denied, and yet the appearance of their 

 undoubted remains both in the greensand or quader-sandstein, 

 and in the Jura formation, is not at all uncommon. It will not 

 be first necessary to call to mind the impressions of leaves in the 

 period of the formation of chalk to which we have already re- 

 ferred on another occasion. Their well known structure, the dis- 

 tribution of their veins, leaves us not a moment to doubt with 

 what to class them. It was more striking to us, however, to ob- 

 serve that M. Brongniart did not hereby think of his own early 

 and numerous observations and remarks. For we find the leaves 

 of many completely undoubted kinds of Dicotyledofia in the sand- 

 stone formation of Hoer on Schonen, mentioned by himself; and 

 the author himself attaches great value to these, as affording evi- 

 dence of the age of the strata. The same appearances are also 

 known to belong to the Jura formation. In the strata of this age, 

 in France and England, we find the presence of dicotyledonous 

 plants frequently mentioned. Desnoyers and Brongniart them- 

 selves knew the same in the Jura oolite of Mamers. Further, the 

 same appearance probably occurs in the strata at Stonesfield near 

 Oxford, so rich in fossils. Mr Webster has also described the 

 abundant appearance of very considerable Dicotyledonous trees 



