126 TRANSACTIONS AND PROCEEDINGS OF TlIK [skss. lxiii. 



evidence derived from Basidiospores and asexual algne 

 must be ruled out of court, and inadmissible in a discussion 

 on Darwinism. 



We have assumed that the plants belonging to the great 

 kingdom of the fungi are descended from alga\ When 

 they left the sea, they neither became animals, wandering 

 about devouring vegetables, or other animals, nor did they 

 remain true vegetables, fixing carbon by the aid of chloro- 

 phyll and sunlight. They adopted a sedentary life, and 

 became either Saprophytes or Parasites. Those which 

 became Saprophytes had no particular need for sex, and 

 have never developed it. If they could not get one kind 

 of rotting matter, they could get another, and could there- 

 fore vary indefinitely. They have, as a rule, become large, 

 and are often beautifully coloured. We know them as 

 Basidiomycetes. 



The Parasites, on the other hand, had to adapt them- 

 selves to the conditions of life of the plant or animal on 

 which they became parasitic. 



To do this, they had to become sexual, for only thus 

 could they preserve a steady permanent type. 



We know them as Saprolegnas, parasitic on fish ; En- 

 tomophthoras, parasitic on insects ; Peronosporas, parasitic 

 on plants. All are sexual, and generally small and ugly. 



The simplest class of the fungi is that of the microbes 

 — a word meaning minute organisms. Tliey are often 

 called Bacteria, from the name of their best known genus. 

 They exhibit spontaneous division, and have a cellulose 

 wall. They may, therefore, be called Schizophytes. 



They have no chlorophyll, and may therefore be called 

 Schixomycetes. 



Must we suppose that Darwin's tlieories apply to these 

 lowly plants ? 



We must presume that fortuitous variation has occurred, 

 in order to explain liow they became fungi, after having 

 been at one time alga.-. We must admit in them the law 

 of selection of the fittest, for many of them differ in shape 

 and size, and in the case of some, which resemble each 

 other in all other respects, we find that they have different 

 properties — some harmless to man, some poisonous ; but 

 being asexual plants, the law of heredity will not repress 



