THE FUNGI 



109 



known. The fruits are also borne underground, and in the genuine 

 Truffles are tuberlike bodies which contain numerous canals or 

 chambers lined with the ascogenous hyphae. In most of the genera 

 there are the usual eight ascospores, but in the genuine Truffle (Tuber) 

 (Fig. 134) the number may be reduced to two, or even a single one. 

 The order is poorly represented in America, but in the Pacific States 

 a number of forms have been recorded. 



Order VI. Plectascineae 



The Plectascinese are, for the most part, saprophytic Fungi, whose 

 well-developed mycelium may be either buried in the nutrient 

 substratum or is superficial. Some of them, e.g. species of Peni- 

 cillium, may produce alcoholic fermentation. In many species 

 conidia of characteristic form are developed, in addition to the asci. 

 The latter in the lowest types, the Gyrnnoascacese, are borne directly 

 on the mycelium, but in most of them closed fruits, somewhat like 

 those of the Tuberinese, are produced ; and these in a few cases have 

 been shown to 



result from the 

 fertilization of an 

 oogonium. 



B 



D 



Aspergillaceae. 

 The most familiar 

 members of the or- 

 der belong to the 

 Aspergillacese, and 

 are known popularly 

 as Blue or Green 

 Moulds from the 

 color of the conidia, 

 which are produced 

 in great numbers. 

 Of these forms, the 

 Herbarium-mould 

 (Asjiergillus herba- 

 riorum) and the 

 common Blue- 

 mould (Penicillium 

 glaucum} are well 

 known (Fig. 135). 

 The latter grows on 

 almost any organic 

 substances, and is 

 the most ubiquitous of all Moulds. From the white mycelium there are sent 

 up delicate upright conidiophores, which in Aspergillus develop a bulbous 

 swelling at the apex, while in Penicillium the conidiophore forms several short 

 terminal branches. From the enlarged terminal body, or from the ends of the 



FIG. 135. A, Penicillium glaucum (X 525). B,Eurotium 

 herbariorum (X 250). C, sexual organs of P. crustaceum 

 (X575). D, spore-fruit of E. herbariorum (X 250). E, 

 ascus (X 500). (C, after BREFELD.) 



