98 Elementary Biology. 



female cells, which we termed respectively sperms and ova. 

 These we found were produced in spermaria and ovaria. 

 Have we anything comparable to this in Fenidllium ? Cer- 

 tainly, the primary spiral filament in the so-called 'fructifi- 

 cation ' is undoubtedly an ovarium, while the secondary 

 spiral is as undoubtedly a spermarium. 1 At this point, 

 however, a certain amount of divergence is observable. The 

 whole contents of the spermarium fuse with or fertilise the 

 contents of the ovarium. Again we notice that the spermarial 

 or male filament is the active or kinetic filament coiling up 

 to meet the terminal portion of the ovarium. 



The phenomena taking place subsequently to fertilisa- 

 tion are also considerably modified. In Fucus the embryo 

 at once developed into the adult plant, in Penicillium that 

 development is postponed ; in fact, the stimulus of the male 

 fertilising matter seems needed for bringing about the forma- 

 tion of ova (fertilised, however) from the protoplasm of the 

 ovarium and its branches ( * asci ' ). The so-called * asco- 

 spores ' are, therefore, the delayed products of sexual union, 

 and for that reason ought to be called embryos, just as the 

 products of sexual union in Fucus were called embryos. 



How shall we exp'ain, then, the occurrence of an asexual 

 method of multiplication ? 



It has been seen -that Pcnicillium is dependent for its 

 life on the obtaining of complex organic food matter, and 

 is unable to decompose carbonic acid and build up organic 

 compounds out of inorganic constituents. Manifestly, there- 

 fore, the food supply of Penicillium is considerably more 

 limited than that of green plants in consequence of its para- 

 sitic habits. Moreover, it has been seen that its sexual 

 method of reproduction is one of considerable complexity, 



1 Brefeld, who first made out the stages in the formation of asco- 

 spores in Penicilliuw, now believes that the process is vegetative and 

 not sexual. De Bary's researches establish beyond doubt that Brefeld's 

 first conclusion is the correct one. 



