348 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



districts. The coral-like Clathrus has its northern limit in 

 the Isle of Wight and Devonshii-e. The largest species occurs 

 in the west coast of Africa, but at present it is little known. 

 It is difficult to conceive what object is answered by the net- 

 work of such species as Phallus Dcemonum. When the pileus 

 first bursts through the volva the meshes are comparatively 

 smaU, but after this, when the hymenial surface and fruit have 

 arrived at their full maturity, the network goes on increasing 

 till it attains considerable dimensions. The structure of the 

 hymenium can be seen only in specimens which have not yet 

 ruptured the volva. The naked spores are seated upon 

 spicules at the top of the sporophores, and are often more than 

 four in number.* 

 ■5. Hypog^i, Berk 



Growing beneath the surface of the soil. Peridium adnate, 

 very rarely separable. Hymenium sinuoso-convolute. 



377. The peculiar characters of this group depend almost 

 entirely upon their subterranean habit. In fact, some are far 

 more closely allied to individuals of other tribes than they are 

 amongst themselves, and it is only in deference to commonly 

 received opinion, and certain general appearances, that I am 

 inclined to consider them as a distinct tribe. Gautieria is but a 

 subterranean S2Mrassis, without, indeed, any attempt at a volva 

 or peridium ; Hymenangiiim and Octaviana are reduced 

 Podaxinei; Melanogaster is nearly allied to ScleroderTna ; 

 while Hysterangiuin is very nearly related to Phalloidei. 

 They all agree in having a sinuous hymenium, and in some 

 cases the cavities are traversed by threads, as in Myxogastres. 

 The nearest approach to a distinct external covering is in Hys- 

 terangium. In other cases the trama and external coat are 

 perfectly confluent. In most of the species the substance is 

 fleshy and becomes drier at maturity, but this is not the case 

 in Hysterangium. In a few instances, as in Hydnangiuni, 

 there is an abundant flow of milky juice when they are frac- 

 tured. The spores in many species accumulate in such num- 

 bers in the cavities, as to make it certain that the spicules 



* Berk, in Ann. of Nat. Hist., vol. iv., p. 155. 



