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their termination in the outer coat of the fungus. Gautieria 

 connects the Hymenogastreee with the Hymenoraycetes, being 

 without a peridium, all the other genera of the former order 

 possessing one, which is however less complex than in most genera 

 of the Gasteromycetes, especially in many of the Lycoperdineoe. 

 In Lycoperdon the peridium is generally composed of two coata 

 closely applied to one another, but distinct in the nature of the 

 tissues which constitute them ; the exterior, far the thickest, ia 

 formed of transparent, spherical or elliptic cells filled with a 

 colourless fluid ; the second, or inner stratum, constitutes the true 

 peridium, and consists of a strong although delicate membrane 

 composed of interlaced threads, the iuner surface giving origin to 

 the capillitium or fertile filaments. The peridium of Geaster is more 

 complex than that of Lycoperdon ; the interior, or proper peridium, 

 corresponds to that organ in the latter genus, but the outer, scissile, 

 covering is of a very complex character. Geaster hygrometricus is 

 clothed at first with a dense, fibrillose, covering, separating into 

 fragments, which, in drying, remain attached to the outer envelope. 

 Tulasne considers this exterior coat as analogous to a mycelium. 

 Beneath this we find a delicate coloured stratum, then another of a 

 white tint composed of bent threads which form the thickened base 

 of the external peridium ; this, again, is covered over all its free 

 surface by a transparent, corneous tissue, which is itself lined by a 

 thick coat of a carbonized nature, and of a vinous colour, adhering 

 to it very firmly at first, but, after the fungus has burst open, 

 separating itself from the internal coat, which remains free within 

 it, the peridium soon after perishing, at least in part, what remains 

 assuming a cup shape. In Polysaccum and Scleroderma, which 

 Corda regards as the types of two different tribes, the protecting 

 tegument is homogeneous and simple ; it consists of a thick coat of 

 a carbonized nature inseparable throughout, the internal wall 

 blending with the substance of the partitions which pass through 

 the interior of the fungus. The peridium in the last named genera 

 is most Hke that of the Hymenogastreee among Hypogees ; in the 

 latter it forms an homogenous tissue which cannot be separated 

 into distinct coats. In Hysterangium the peridium is delicate, but 

 flexible, and of remarkable tenacity ; being composed of elongate 



