500 BRITISH FUNGI 



tion to the gills of agarics, and bear the basidia. Nearly all the 

 species are strong-scented, the smell in some instances being very 

 agreeable, that is, from the human standpoint, as in the edible 

 truffles ; in other examples the smell is very strong and nauseous, 

 especially when the fungus is mature. Growing underground and 

 entirely lacking the usual methods for effecting the dispersion of 

 the spores, the truffles are eaten by various animals, more especially 

 rodents, and by this means the spores, which do not suffer in pass- 

 ing through the alimentary canal of an animal, are dispersed. 

 The strong smell exuded at maturity is for the purpose of indicating 

 to animals the whereabouts of the subterranean fungi. Dogs and 

 pigs are trained to hunt for truffles, being guided by the strong 

 smell emitted by the fungus. 



The most highly prized edible species, or truffles, are included 

 in the genus Tuber. Our best native species is Tuber cestivum, 

 which occurs in fair quantity in a few districts, more especially 

 under beeches on Salisbury Plain. The neighbourhood of Patching, 

 near Arundel, Sussex, was at one time noted for its fine 

 truffles. 



TUBERACE.E 



Ascophore subterranean, subglobose or irregular in form, wall 

 fleshy or leathery, continuous or variously perforated ; asci con- 

 taining 1-8 spores ; spores i-celled. 



Key to the Families 



Gleba breaking up into a blackish powdery mass of spores at 

 maturity. i. Elaphomycetece. 



Gleba not becoming powdery, but becoming lacunose or caver- 

 nose owing to the persisting walls of the gleba. 2. Tuberecv. 



I. ElAPHOMYCETE/E 



Elaphomyces 



Ascophore irregularly subglobose or depressed, wall thick and 

 firm ; asci subglobose ; spores coloured, forming a lilackish dusty 

 mass when mature. 



This is the only genus included in the family Elaphomycetece, 

 and is distinguished by the early disappearance of the dissepiments 

 of the gleba and the walls of the asci, the spores filling the cavity 

 of the fungus with a blackish dusty mass at maturity. 



E. anthracinus. — Ascophore subglobose, blackish brown, firm and 

 hard, minutely wrinkled, up to ih in. diam. ; mycelium usually 

 abundant, brownish ; asci subglobose ; spores globose, minutely 

 wrinkled, blackish brown and opaque, 16-20 fi diam., mixed with 

 fine cobweb-like threads. 



