FLORA OF THE CARBONIFEROUS EPOCH. 



67 



Ficr. 54. 



earth when coal was formed must be very limited, when we 

 reflect how seldom the fructification of coniferous trees has 

 been met with in the coal-measures. 

 A very doubtful fragment, supposed 

 to be a cone, is given in Lindley and 

 Hutton's work, under the title of Pinus 

 anthracina ; but it is believed by Car- 

 ruthers to be a fragment of a Lepido- 

 dendroid branch. Lyell never saw a 

 fossil fir-cone of the Carboniferous 

 epoch, either in the rocks or museums 

 of North America or Europe. Bunbury 

 never heard of any other example than 

 that noticed by Lindley and Hutton. 

 Principal Dawson is disposed to think 

 that the suberin of cork, of epidermis in 

 general, and of spore-cases in particular, is a substance so rich 

 in carbon that it is very near to coal, and so indestructible and 

 impermeable to water, that it contributes more largely than any- 

 thing else to the mineral. Sir Charles Lyell remarks — "To pre- 

 vent ourselves, therefore, from hazarding false generalisations, 

 we must ever bear in mind the extreme scantiness of our present 

 information respecting the flora of that peculiar class of sta- 

 tions to which, in the Palaeozoic era, the coal-measures pro- 

 bably belonged. I have stated elsewhere my conviction that 

 the plants which produced coal were not drifted from a dis- 

 tance, but nearly all of them grew on the spot where they 

 became fossil. They constituted the vegetation of low regions, 

 chiefly the deltas of large rivers, slightly elevated above the 

 level of the sea, and liable to be submerged beneath the 

 waters of an estuary or sea by the subsidence of the ground 

 to the amount of a few feet. That the areas where the car- 



Fig. 54. PotJiocites Grantoni, Paterson. a, Spike natural size ; 

 6, Portion of spike magnified ; c, Perianth, 4-cleft, magnified. 



