Fungi. 211 



to a halt in winding up the organism, as it were, leaving it in a state of 

 tension or erethism, ready to unwind and start off again upon the 

 renewal of the proper conditions, or, in other words, this undifferentiated 

 cell must by turns grow and rest, unwind and wind up, become the leaf 

 cell and the seed. 



When an organism, as a Desmid, for example, comes to have spores, 

 we may conclude that a differentiation has taken place by which the 

 growing by the continuous division and multiplication is exclusively 

 confined to one set of cells, while the function of reproduction or of the 

 renewal of growing after it has been stopped is transferred exclusively 

 to another set. There is probably an intermediate stage in which there 

 are cells exercising either function, as compelled by circumstances. 



We thus find a strong parallelism between the Fungi and the lower 

 algae in morphology and modes of reproduction. The resemblance is 

 sometimes so strong between them that naturalists do not agree on 

 which side of the line to place some of them. One order of the Phy- 

 somycetes; viz., the saprolegniei, is claimed to be algae, by some authors. 

 Where the difference is pronounced,' it consists almost, if not entirely, 

 on the fact of the presence of chlorophyl in the Alga, and its absence in 

 the Fungus. And there are the intermediate organisms in which, while 

 chlorophyl in limited amount is present, it is yet doubtful whether it is 

 the sole dependence of the organism for obtaining food. It is eas} T to 

 see how such a plant having a case through which, by endosmose, it is 

 capable of taking up fluid saturated with already elaborated vegetable 

 matter, and also chlorophyl organs, of limited capacity, for seizing car- 

 bon from the atmosphere, might be placed under conditions in which it 

 would get a better supply of food already elaborated than it could 

 elaborate for itself. The very fact that any food could be got without 

 the use of the chlorophyl function, would, to a greater or less extent, 

 supersede and discourage its use, and such discontinuance of the use of 

 the function must result, as in all such cases, in its final extinction, fol- 

 lowed by the loss of the organ. The Fungus has unquestionably passed 

 through this experience, and in thus quitting hard work and taking up 

 easy work it illustrates the materialistic economy which governs the pro- 

 cesses of differentiation. That is, whenever there is more than one way 

 of. accomplishing a vital end, the differentiations favor the cheapest way. 



It must occur to everyone that essentially there is much in common 

 between the Fungus and animal life. Especially is the animal parasite 

 essentially like the Fungus parasite-on-an-animal, even to the food he 

 consumes and the functions he performs. But in its dependence on 

 getting food ready prepared into proteids and amyloids, in its inability 

 to make starch, or decompose carbonic acid gas, and in its requirement 

 of free oxygen, the Fungus is like all animals. We are very close here 



