CRYPTOGAMS 



413 



stalk swollen at the base ; Russula emctica, with a red pileus and white lamellae ; 

 Lactarius torminosus, having a shaggy, yellow or reddish-brown pileus and white 

 milky juice. 



Rozites yongylophora, 

 found in South Brazil, is of 

 especial biological interest. 

 According to A. HOLLER, this 

 species is regularly cultivated 

 in the nests o f the leaf-cutting 

 ants. Its mycelium produces 

 spherical swellings at the ends 

 of the hyphse, which become 

 filled with protoplasm, the 

 so-called Kohl-rabi heads, and 

 serve the ants as food material . 

 The ants prevent the develop- 

 ment of the accessory conidial 

 fructifications peculiar to this 

 fungus, and thus continually 

 maintain the mycelium in 

 their nests in its vegetative 

 condition. The fructifica- 

 tions, which rarely occur on 

 the nests, resemble those of 

 Amanita muscaria, with 

 which Rozites is nearlyallied. 

 AccordingtoHoLTERMAN,the 

 mycelium of Agaricus rajap 

 is cultivated in their nests by 

 termites in tropical Asia ( 81 ). 



ECONOMIC USES.- Poly- 

 porus fomentarius (FUNGUS 

 CHIRURGORUM). Polyporus 



officinalis ( Boletus laricis) gives AGARICUS ALBUS, AGARICINUM, and ACIDUM 

 AGARICINUM. 



Order 6. Gasteromycetes ( w ) 



The Gasteromycetes are distinguished from the Hymeuomycetes by their closed 

 fructifications, which open only after the spores are ripe, by the rupture of the 

 outer hyphal cortex or PERIDIUM. The spores are formed within the fructifications 

 in an inner mass of tissue termed the GLEBA ; it contains numerous chambers, 

 which are either filled with loosely interwoven hyphae with lateral branches 

 terminating in basidia, or their walls are lined with a basidial hymeuium. 



The Gasteromycetes are saprophytes, and develop their mycelium in the humus 

 soil of woods and meadows. Their fructifications, like those of the Hymenomycetes, 

 arc raised above the surface of the substratum, except in the group of the Hymeno- 

 gastreae, which possesses subterranean, tuberous fructifications resembling those of 

 the Tuberaceae. 



The fructifications of Sclcrodcrma vulgarc (Fig. 363, 1) have a comparatively 

 simple structure. They are nearly spherical, usually about 5 cm. thick, and have 

 a thick, light brown, leathery peridium which finally becomes cracked and 



FIG. 3C2. Aiiianita Imlbosa. (J nat. size.) Potsoyoi'f. 



