CLASSIFICATION 479 



portion of the fungus from injury against both hving enemies and 

 physical dangers ; also the most certain and economical means by 

 which the spores are diffused. Both these ideas are carried out to 

 perfection in the present family. The hymenium or spore-producing 

 portion of the fungus is fully developed and the spores are quite 

 mature, while yet hermetically sealed within the thick-walled 

 gelatinous volva, which itself remains buried in the ground until 

 this process is completed. At this stage the structural elements 

 of the hymenium, the basidia that bore the spores, etc., become 

 resolved into a very strong-smelling, olive-green, viscid mass con- 

 taining the very minute spores embedded in its substance. The 

 second stage, providing for the dispersion of the spores, now com- 

 mences. Owing to the sudden elongation of the receptacle or por- 

 tion bearing the hymenium, the volva is ruptured and the recep- 

 tacle bearing its mucilaginous, spore-laden mass is elevated into 

 the air. The strong-smelling mucus is as sweet as saccharine to 

 the taste, and is much relished as food by various kinds of flies, 

 who unconsciously disperse the spores, partly by means of the 

 small amount of mucus containing spores that adheres to their feet 

 and proboscides, and it has been proved also that spores, after 

 having passed through the body of a fly, are yet capable of germina- 

 tion. In most instances the sporophore is red or orange in colour, 

 which, combined with the strong, penetrating smell, serve as indi- 

 cations or advertisements to flies as to their whereabouts. After a 

 specimen of Ithy phallus impudicus has just emerged from its volva 

 it is usually more or less covered with feasting flies. It is interest- 

 ing to note that, whereas colour and smell are agents employed by 

 many flowering plants for securing cross-pollination, they are 

 used by certain fungi for securing the dispersion of their 

 spores. 



The Phalloidaceas are essentially a tropical family with less than 

 a dozen outliers in Europe. There are only three British species. 

 Now and again tropical species occur in this country, having been 

 introduced with exotic plants, grain, etc. 



Key to the Genera 



Pileus free from the stem at the sides ; apex of stem with an 

 opening. Ithyphallus. 



Pileus gro^^•n to the cap throughout ; stem ^\•itllout an opening 

 at the apex. Mutinus. 



Stem with 4-6 lobes at the apex, bearing the hymenium. 



LysiiTHS. 



Stem with a flattened disc at its apex, from the margin of which 

 sjiring a number of spreading lobes or rays. Ascrcc. 



Receptacle bearing the hymenium forming a hollow s})here, the 

 1 ounding wall consisting of an irregular network. Clailirus. 



