372 



BOTANY 



angioearpous, and enclosed during their early stages. In the "Fly Mushroom," 

 Amanita muscaria, the volva is well developed, and after its rupture it is still trace- 

 able in the white scales conspicuous 

 on the red surface of the pileus, and 

 also on the swollen base of the stalk 

 (Fig. 297). 



In addition to the volva many 

 Agaricineae develop a so - called 

 VELUM, consisting of a thin mem- 

 brane of hyphal tissue which extends 

 in young fructifications from the 

 stalk to the margin of the pileus, 

 and encloses the hymenial lamellse. 

 This covering is afterwards ruptured, 

 and remains as a pendulous ring of 

 tissue or aknulus infekus encirc- 

 ling the stalk. This ring is very 

 perceptible on the stalks of Armil- 

 laria mellea (Fig. 291) and the 

 cultivated mushroom or champignon 

 Psalliota campestris (Fig. 298). 



In the majority of Agaricineae 

 the lamellae are developed as free 

 outgrowths from the under side of 

 the pileus. In the case of Amanita 

 muscaria the manner of their de- 

 velopment is different, and they arise 

 by the differentiation of a homo- 

 geneous hyphal tissue in the interior 

 of the dome-shaped rudiment of the pileus resulting in the separation of the hyphas 

 into radial plates. The lamellse thus formed are merged at the margin of the rudi- 

 mentary pileus into a neutral layer of united 

 hyphse connected with the stalk. As the 

 pileus expands, this layer becomes loosened 

 from the lamellse and remains hanging to the 

 stalk as an upper ring, annulus supekus (Fig. 

 297). 



Many of the Mushrooms found growing in 

 the woods and fields are highly esteemed as 

 articles of food. Of edible species the follow- 

 ing may be named : the common Field-Mush- 

 room, now extensively cultivated, Psalliota 

 campestris (Fig. 298), with whitish pileus and 

 lamellse at first white, then turning flesh- 

 colour, and finally becoming chocolate-coloured ; 

 CantJiarellus cibarius, having an orange-coloured 

 pileus ; Lactarius deliciosus, which has a red- 

 dish-yellow pileus, and contains a similarly 

 coloured milky juice in special hyphal tubes ; 

 Lepiota procera, whose white pileus is flecked with brown scales ; Amanita 

 in the south of Europe, related to the poisonous species Amanita 



Fig. 297. — Amanitamuscurki,. (£nat. size. Poisonous.) 



-5A*&rr& 



Fro. 29S.— Psalliota canvpestris (=AgaHcus 

 campestris). To the right, a young fruc- 

 (Reduced.) 



tification. 



caesarea, 



