156 The Ottawa Naturalist. [March 



tion of this is the fact that of all the edible, fleshy fungi known 

 and desired by man, we have learned the conditions of growth 

 of only one, the common Meadow Mushroom, and in spite of 

 many long continued efforts at cultivation by botanists and 

 epicures, not another kind lias as vet been tamed. 



The fungi "seek darkness rather than light " and usually the 

 only parts which come into the light are those reproductive 

 structures which quicklv break down into minute fragments to 

 be scattered by the wind and water. These colorless plants are 

 able to live only by absorbing other protoplasmic substances, 

 either dead or alive. They are therefore not honest in getting 

 their livelihood, but take it from others, although it is true that 

 in some instances they give valuable service in exchange. 



Note that in the forms of life thus far mentioned there is no 

 such phenomenon as sex. But when we turn to those which have 

 learned to tolerate light and protect themselves from its harmful 

 power, we at once come into contact with another method of 

 reproduction, and this method has proved so advantageous that 

 all but the lowliest forms of life have adopted it. Sexual re- 

 production differs from that described as belonging to most fungi, 

 in that each offspring has two parents instead of one. In place 

 of fragments (spores) falling from one individual, and each 

 spore growing into an individual like the parent two fragments 

 are necessary, usually one from each of two different individuals, 

 these spores fuse together into one, and this resulting egg has 

 the power of growing into an individual like the parents. 



Such an arrangement is evidently much less simple than 

 the other, the sexual way, but, as said before, it has become the 

 method among all higher organisms. There must be very im- 

 portant advantages connected with it. We are not able to give 

 clear and complete reasons for the general adoption of the sexual 

 method, but one advantage has been indicated by contrast. 

 In sexual reproduction say in Spirogyra, one of these simple 

 plants fragmentsof two individuals take part in the formation of 

 each new Spirogyra individual. The parent filaments of Spirogyra 

 being free floating plants, did not grow under exactly similar 

 conditions and are not likely to he offspring of the same two 

 parents. Hence they will have quahties which are somewhat 

 unlike. This variety of quali + ies will be inherited by their off- 

 spring, and the offspring will thereby have more power of 

 adapting itself t^ an though derived from a single parent having 

 but one set of oua'ities. As t u c voting Spirogyras float about 

 they will certainlv 1 a ea be+ + or rover of adapting themselves 

 to the varietv o* < n Htions thev will meet, than has the young 

 fungus, which 1 aried assortment of malities, derived 



I I'n a varied a ' ' , "" ,+ of r-^^e^fc^. It is certain this is an 



