1274 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXI. 



plants, such as lichens and algee, by the absence of the green 

 colouring matter, called chlorophyll. It is for this reason that 

 they assume all possible colours, except green. Being devoid of 

 chlorophyll they cannot assimilate carbon dioxide, but must take 

 up their carbonaceous food in the form of rather complex com- 

 pounds, which they find on living or dead organic substances v. cj. 

 leaves, wood, dung, humus, decayed fruits, paper, insects, etc. 

 Accordingly, some are parasitic, such as the Rusts and Smuts, 

 and absorb those complex carbon-compounds from other living 

 organisms, whether plants or animals. Others are saprophytic, 

 absorbing those compounds from the remains of dead organisms as, 

 V. CJ. the numerous and often large mushrooms which grow on 

 humus or leaf soil in forests, — or from organic substance formed 

 by living organisms. Examples of the latter are the Yeasts and 

 Moulds which make their appearance on juicy fruits, saccharine 

 liquids, etc. 



This is not the place to give a systematic account of the differ- 

 ent classes of fungi. We shall confine ourselves to giving the 

 general characteristics of some more important groups. 



Excluding from the outset the Schizomycetes (y. g., Bacilli), 

 Myxomycetes and Phycomycetes, we shall consider the fungi 

 known as Mushrooms, Toadstools, Pufiballs, Yeast, Moulds, 

 Mildews, Rusts and Smuts. 



These may be divided into two classes, the Basidiomycetes and 

 Ascomycetes. In the Basidiomycetes the spores are borne free on 

 so-called basidia (Fig. 1 ), whilst in the Ascomycetes the spores, 



Fig. 1. — Section of a gill of an Agaric (left) and of a pore of a 

 Polyporus (riglit), showing the basidia (a) which bear 

 on 4 sterigmas (b) the 4 spores (c). 



