LICHENS. 201 



beautiful character. " Some of the rocks," he says, 

 " around the Lake of the four Cantons in Switzerland, 

 cannot be sufficiently admired on this account."' This 

 lichen affects trap rocks ; we found it on such in the Isle 

 of Arran. 



The Eocks Lecidea (Petrcea, Plate XIV., fig. 1). is 

 scarcely less attractive, its crust is white, and its 

 Apothecia black and elongated, and clustered in lines 

 diverging from a centre. We found it on a remarkable 

 excursion to the Cheese Wring, in Cornwall, where huge 

 masses of granite rock are heaped in a circle, bearing 

 evidence of druidical origin. Great numbers of quarry- 

 men were engaged in excavating the granite in the 

 neighbourhood, and again and again as we searched for 

 flowers and lichens, the ground beneath us was shaken as 

 with the shock of an earthquake, owing to the blasting 

 necessary to detach the granite blocks. 



On mossy trunks, both in Yorkshire and Kentish 

 woods, we have often found the Yellow Lecidea (L. lutea, 

 Plate XIV., fig. 5). Here the crust is pale yellow, and 

 the Apothecia darker yellow. Black dots of varying 

 size, surrounded by a scarcely perceptible grey crust, 

 formed patches on the limestone rocks in beautiful 

 Swaledale (L.atrata, Plate XIV., fig. 4), and others seemed 

 to have eaten into the stone, and buried themselves each 

 in a little nest of its own excavation (L. inimeria, fig. 3). 

 Mope's Den, a beautiful wood in the Bedgebury Estate, 

 near Hawkhurst, furnished us with a green Lecidea 

 (L. parasema, Plate XIV., fig. 6), which grew on the 

 trees, and bore black receptacles ; whilst stones lying on 

 damp places on Starvegoose heath supplied the Bog 



