REPRODUCTION. 625 



observations, notably those of Brefeld, and it would appear that 

 the fructifications on which the spores (basidiospores) of these 

 plants are borne find their homologues, not in the sexually pro- 

 duced, but in the normally asexually produced fructifications of 

 the other Fungi. The Basidiomycetes appear, in fact, to be 

 altogether asexual. Not only are they destitute of sexual 

 organs, but they lack even that trace of sexuality which is 

 indicated in the asexual Ascomycetes, such as Claviceps, etc., 

 by the production of fructifications resembling those which are 

 the product of the sexual process in the sexual Ascomycetes. 

 The fructifications of the Basidiomycetes are simply organs for 

 the asexual production of spores. 



The result of the sexual process is, as we have seen, in all 

 cases the production of one or more spores, but the effect of 

 the sexual process is not necessarily confined to the cells or 

 organs which directly take part in it. In very many cases it 

 stimulates adjoining organs to active growth, leading to the 

 formation of the structure which is termed the Fruit. For 

 instance, in various Mucorini an outgrowth of filaments, form- 

 ing a complete (Mortierella) or incomplete investment to the 

 zygospore, takes place after conjugation : in Coleochaete the 

 oogonium becomes surrounded, after the fertilisation of the 

 oosphere, by a cellular investment formed by outgrowths from 

 adjacent vegetative cells ; and, as we have already learned, a 

 cellular investment is formed in a similar manner round the 

 fertilised procarpium of most Florideae, and round the fertilised 

 ascogonium of most of the sexual Ascomycetes, resulting in 

 the formation of the cystocarp in the former case, and in that 

 of the apothecium or perithecium in the latter. The most 

 familiar instance of fruit-formation is that occurring in the 

 Phanerogams. Here, in most cases the carpels, in some the 

 perianth-leaves, and in some the floral receptacle (torus} grow 

 actively after the fertilisation of the oospheres has taken place, 

 giving rise not infrequently to a mass of succulent parenchy- 

 matous tissue. Something of the same kind, though less 

 marked, is to be observed in the archegoniate plants. In 

 these, the archegonium grows considerably, after the fertilisa- 

 tion of the contained oosphere, especially in the Muscineae in 

 V. 40 



