Parsons : The Kfjects of Hcaili I'ii'cs on Vegciation. 125 



•ground, a belt in which the green heather lay loose, as if mown 

 •off by a scythe, upon the smouldering surface for some little 

 time ]:)efore being sufficientlv dried to catch lire and l)urn. 



The plants which appear during the following season on the 

 burnt ground are of two classes : — ist, deep rooting and thick- 

 rooted plants, whose rootstocks and rhizomes have escaped 

 being killed by the fire, such as the gorse, heather and bracken, 

 and other herbaceous plants with deep-spreading rhizomes, as 

 Epilobiiini angiisiifolinm ; 2nd, wind-borne plants which can 

 grow on a soil destitute of organic matter. Of these, the first 

 to take possession of the ground are the mosses, Ceratodon 

 purpitreas and Funaria hygrometrica, the latter of which has an 

 especial affection for materials that have been burnt, as bricks, 

 lime, rubbish, cinders and charcoal heaps. These mosses form a 

 wdde-spreading brightly coloured carpet over the blackened soil, 

 and by their decay furnish the humus necessary for the growth 

 of the higher plants. In our comparatively dry climate 

 lichens are of slow growth, and large forms like Cladonia have 

 not time to establish themselves in such places before the ground 

 is again occupied by phanerogamic vegetation, but Lecidea 

 decolorans spreads like the mosses over the bare barren surface. 

 Of flowering plants, the first to take possession of the ground 

 are the hair grass [Aira flexuosa), Senecio sylvaticus, and the 

 sheep's sorrel {Rttniex acetosella). All of these appear able 

 to grow in soil containing a minimum of nutritive matter ; 

 the Senecio seeds are transported by a feathery pappus, and the 

 sorrel has a creeping rhizome which may have escaped the 

 fire. Seedling plants of heather, gorse and birch, and of grasses 

 and other herbaceous plants later spring up, and eventually 

 the ground is covered with a vegetation resembling that which 

 existed before the fire. But it is probable that some species 

 which grew on the area before the fire may not re-appear ; 

 and the frequency of these fires owing to the increased resort 

 of holiday-makers to the commons, may be one of the reasons 

 why many plants mentioned in old records are no longer found 

 growing there. 



Still they come, and go ! For some months Mr. E. K. Robinson in 

 the pages of Country Side, and its hopeful offspring, has been correcting 

 Darwin ! Amongst the subjects discussed was ' the survival of the fittest.' 

 Both Cowitvy Side and Science Gossip have now ceased to be. R.I. P. 



igio Mar. i. 



