300 H. MARSHALL WARD. 



strong hereditary tendency to produce sexual organs, &c., noight 

 become lost, if such organs for any reason became superfluous. 



This, however, brings us at once to the last object of the 

 present essay ; and I propose to show that it is probable that 

 the sexuality of the higher Fungi has disappeared, because its 

 purpose has been equally well or better attained otherwise than 

 by means of sexual organs. 



Preliminary to this it will be necessary to be quite clear as 

 to what sexual organs and the sexual process essentially are. 



The two points common to all the cases of sexual reproduction 

 which have been directly observed are the following : 



1. A larger or smaller quantity of protoplasmic material 

 passes from one portion (the male orgaq) of the same or another 

 individual, into the protoplasm contained in another portion 

 (the female organ). 



2. The protoplasm contained in the female organ therefore 

 becomes capable of further development ; either at once, or, 

 more generally, after undergoing a period of rest. 



It is not necessary to quote the numerous cases of observed 

 analogies between the sexual reproduction of animals and 

 plants ; but will suffice to note that the essential in the sexual 

 process is always the addition of a portion of protoplasm from 

 the male, to the protoplasm of the female. 



But this is not all. It is now well established in embry- 

 ology that the normal ovum, or female mass of protoplasm, is 

 incapable of further development until it has received the 

 protoplasm of the male ; that the latter, in fact, incites the 

 former to further development. In many cases, indeed, the 

 protoplasm of the egg or ovum gets rid of a small portion of 

 its substance, as the " polar bodies," as if to make room (so to 

 speak) for the substance coming to it from the male.^ 



While in the higher organisms we can distinguish the male 

 elements — spermatozoa, antherozoids, &c., only in so far that 

 they are much smaller and more numerous than those of the 

 female organs ; we find that in the lower forms of life even 



^ That something of the same kind takes place in the Saprolegnise is 

 suggested in ray paper on this group, ' Quart. Journ, Mic. Sc.,' 1883. 



