Order Hymenomtcetes. Tribe Pileati. 



Plate XXI. 



POLYPORUS DRYADEUS, p.r.o.. 



False Amadou. 



Gen. Cliar. Hymenium concrete with the substance of the pileus, consisting of sub-rotund pores, with thin 

 simple dissepiments. Name from woXis, many and n-dpos, a. pore in allusion to the numerous pores of the hjTnenium. 



Spec. Char. Polyporus deyadeus. Sessile at the foot of oaks, forming imbricated, u'regularly confluent 

 masses from one foot, to two feet or more across ; each main division of the pUeus is from eight inches to a foot in 

 diameter, and from two to thi-ee inches tliick ; rather soft, grossly tuberculated, the margins swollen, resembling a 

 honey-comb, being filled with pits which at first contain drops of glutinous sUghtly astringent, sub-acid liquor ; as 

 this dries the edges become black and the pits disappear. In youth the whole plant is pale grey with lemon-coloured 

 or whitish margins, in its after-growth cinnamon-brown both surfaces becoming covered with a velvety grey-white 

 substance, like the bloom of fruit, receiving the minutest impression of the Eungus, and turning brown where 

 touched. The pored surface is nearly plane, grey-cinnamon, the pores are extremely minute, the tubes very long, 

 particularly near the base, where they measm-e from a half to three-quarters of an inch in depth ; the mass of pores 

 contracts in di'ying forming deep cracks down to the fibres of the pileus which run at nearly right angles to them. 

 The substance of the j^ileus when dry is fibrous, not corky, reddish brown as well as the tubes. The whole plant 

 is heavy Vhen fresh, but loses much of its weight and volume in drying. It grows very quickly, but a pileus of the 

 previous year sometimes endures thi-ough the winter, and new growth takes place from it. It is at most biennial. 

 PoLYPORCS dnadeus, Fries, Berkeley. 

 Boletus dryadeus, Persoon. 

 pseudo-igniarius, BuUlarcl, 



Hah. At the foot of an aged oak, Hayes; August. 



We have before mentioned that the tribe Polyporus was formerly included in Boletus, but removed from 

 that class by Fries ; Boletus remaining the title of the soft-fleshed family with central stems, whose tubes 

 easily separate from the distinct flesh of the pUeus, while Poli/jjorus includes those more or less coriaceous 

 and generally parasitic individuals, the pores of which are, as in Boletus the orifices of tubes ; but whose 

 tubes are concrete with the substance of the pileus, and cannot be pulled away fi-om it, even when, as in the 

 case of P. dryadeus our present subject, the tubes bend away at right angles to the horizontal fibres of the 

 pileus. 



" Hitherto ", says BuUiard, " tliis Boletus has been confounded with the Amadou, which error would 

 not have taken place if it had been remembered that the Amadou grows very slowly, that it has very short 

 tubes, and that they are never separated by crevices whether fresh or dry ", other distinctions he gives, taking 

 much pains to set at rest which fungus is the valuable article to wliich modern surgery is so much indebted. 



