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characterize the orders and genera contained in the family it may 

 be well to make a few observations on their analogies, their mode 

 of growth, and general oeconomy. The author of the " Outlines" 

 heads the family with the order Hypog^i, or subterranean fungi. 

 M. Tulasne, in his beautiful monograph of this order, observes that 

 light is, generally speaking, more necessary to vegetables than to 

 other organized beings, that there are, nevertheless, certain plants 

 which exist without ever receiving its beneficial influence, or which 

 are deprived of it during a considerable part of their period of 

 growth ; and it is among fungi chiefly that we meet with this 

 abhorrence of light, or, at least, with a preference for a partial 

 obscurity. Almost all fungi proceed from a mycelium of a 

 filamentous or corky nature spreading beneath the soil or under 

 the bark of trees, in each case in situations devoid of light ; this 

 mycelium may be regarded as aualagous to the subterranean organs 

 of other vegetables, and if, like them, it pursues its own functions 

 in the dark, it generally requires light for the perfecting its re- 

 productive portion. Thus the mycelium of an Agaric or Polyporus 

 either remains sterile, or produces only incomplete or monstrous 

 pilei when growing in dark caves or mines. Sometimes it is not 

 the mycelium only which is developed in the dark, but the perfect 

 fungus arising from it shares for a considerable period its obscure 

 habitation. Many Agarics, for instance, complete nearly their whole 

 development beneath the suiface of the gi'ound, thus causing an 

 inattentive observer to suppose that they assume their full 

 proportions in a night, whilst in truth they occupy a considerable 

 time in attaining them. Many of the Gasteromycetes present a 

 similar mode of growth ; thus all the species which are provided 

 with a general envelope, as Phallus, Clathrus, and certain of the 

 Lycoperdons, the Geasters, Tulastoma, and others, pass the time of 

 maturation underground, and only appear above the surface to 

 present their spores to the ordinary means of their dissemination. 

 Others of the Gasteromycetes continue all their lives in a partial if 

 not complete abstraction from the influence of light. Of this kind 

 are the Hymenogasters, which seem to be in this respect inter- 

 mediate between the Lycoperdons and the Truffles. The genus 

 Hysterangium, however, offers an instance among the Hymeno- 



