1 70 CRYPTOGAMI AFUNGI. 



" see non elves mo," another explanation has become ne- 

 cessary, and the only good one which has been ottered is 

 that which attributes them to the peculiar manner of 

 growth which this and one or two other agarics affect. 

 They spring up in circles. Each circle seems to exhaust 

 the soil of some peculiar nourishment necessary for the 

 growth of the fungi, and is rendered incapable of produ- 

 cing a second crop. Hence the circle must necessarily 

 enlarge, for " the defect of nutriment on one side, would 

 necessarily cause the new roots to extend themselves 

 solely in the opposite direction, and would occasion the 

 circles of fun^i continually to proceed by annual en- 

 largements from the centre outwards. An appearance of 

 luxuriance of the grass would follow as a natural conse- 

 quence, as the soil of an interior circle would always be 

 enriched by the decayed roots of the fungi of the pre- 

 ceding year's growth " Dr WITHERING was the first to 

 offer this explanation of a very curious phenomenon, and 

 it seems satisfactorily established by the subsequent obser- 

 vations of Dr WOLL ASTON. 



28. A. peronafus, stalk cylindrical, woolly, wood-brown, tough ; 

 pileus convex or campanulate, obtuse, wood-brown, very thin ; 

 gills wood-brown, rather distant, 4 or 8 in a set, ventricose< Sow. 

 Fung. t. 37. GREV. Fl. Edin. 379. 



Hob. In woods, firmly attached by its woolly root to de- 

 cayed leaves and straws. Blackadder plantations. Sept. 



Stalk as thick as a goose quill, 3 inches long Distinguished 

 by its uniform brownish colour, the woolliness of the stem, 

 the thinness of its flesh and its obtuse campanulate leather- 

 like pileus, which is 2 inches in diameter. 



* * Stalk central and hollow. 

 t Gills fixed. 



29. A. laccatus, gregarious, dry, coriaceous ; stalk cylindrical, 

 twisted, roughish ; pileus irregular, convex, dimpled in the cen- 

 tre, roughish ; gills distant, thick, broad, somewhat decurrent. 



Var. 1. of a uniform reddish flesh colour GREV. Fl. Edin. 

 377; Crypt. FL t. 249. Ag- farinaceus, WITH. iv. 272. Sow. 

 Fung. t. 208. HOOK. Scot. ii. 22. 



Var. 2. stalk thickened upwards ; gills purple. 



