Sketch of the Class Fungi. 



113 



from the peridium, remains under the form of free filaments which 

 are dispersed with the sporidia, and that in which they form by their 

 union the walls of the cells in which the sporidia are contained. 

 This latter circumstance takes place especially in the subterraneous 

 indehiscent Lycoperdons. 



The genus Polysaccum, DeC, has a common peridium, in the 

 fleshy cellular mass of which appear at first amygdaloid, extremely 

 soft and viscid bodies. As the fungus increases they become con- 

 sistent, and are at length changed into peridiola, in the interior of 

 which the complete evolution of the spores observed by Corda (Ic. 

 Fung. ii. p. 24. t. 12.) takes place. The other species of the sub- 

 terraneous genera offer almost the same morphosis. 



The sporidia differ very little from those of the preceding tribe. 

 Some have an umbilicus or hilum, and some retain the thread or 

 cord (funiculus), which however is generally wanting. Most are 

 smooth, but some are verrucose. I have already said, that in their 

 pulverulent state they are generally mixed with the mass of fila- 

 ments from which they spring. Sometimes this powder occupies 

 the whole cavity, sometimes only a more or less circumscribed por- 

 tion of the peridium. A dry state of the atmosphere is most 

 favourable to the dispersion of the sporidia, and the wind the most 

 effectual agent. In the subterraneous species, where they are ag- 

 glutinated by the drying up of the viscid matter which assisted in 

 their evolution, strong and continued rains are probably the most 

 efficient. 



Almost all the species grow either upon or beneath the earth ; 

 Tulostoma exasperatum, however, and a very few others live on half 

 rotten wood. Some are found exclusively in sand*. They have 

 their centre in the temperate regions of the two hemispheres. Their 

 use is very limited. Some authors affirm, that in certain parts of 

 Italy many sorts of puffball are eaten fried while they are still 

 fleshy. Deer and pigs are reported to root up the Elaphomyces. 

 The sporidia of Polysaccum tinctorium are used in the Canaries to 

 dye wool and silk. 



The Angiogaslres comprise, as we have seen, three tribes united 

 by a common character, sporidia never pulverulent ; they are, how- 

 ever, distinguished by marked differences. Thus, the Nidulariacece 

 have their sporidia enclosed in proper sporangia ; in the Tuheracem 

 they are contained in the thickness of the folds of the peridium ; 

 lastly, in the Phalloidea: they are dispersed in a foetid mucilage 

 which clothes the receptacle. 



The Nidulariacece comprise a very small number of genera, all 

 having a double peridium. The outer is called uterus ; it varies in 

 form, which sometimes resembles a cup or little goblet (e. g. Nidu- 

 laria), sometimes is spherical (e. g. Arachniori) , sometimes hemisphe- 

 rical (e. g. Polyangium) ; and as regards consistence, it is cottony, 

 slightly fleshy, coriaceous or membranaceous. The inner, separable 

 or intimately united with the first, is most frequently papyraceous 



* Podaxon cascinomalis is found on ant-nests. — M. J. B. 

 Ann. § Mag. N. Hist. Vol.ix. I 



