CHAPTER VI 

 M ON OBLEPH ARID ALES 



The members of this order differ strikingly from the Saproleg- 

 niales in that the antheridium frees ciliate male cells (antherozoids, 

 spermatozoids, sperms) which swim to the oogonium and 

 fertilize the oosphere. Since this type of fertilization occurs 

 nowhere else in the fungi the group is of unusual interest to the 

 student of phylogeny. That school of mycologists which 

 regards the fungi as a heterogeneous group of degenerate forms, 

 derived at various points from different types of the algal series, 

 finds in this order a convenient intermediate type connecting 

 the Saprolegniales with such algae as Vaucheria and Oedogonium 

 in which fertilization by spermatozoids occurs. Those students 

 who prefer to derive the higher Phycomycetes from the lower 

 see in the isogamic fusion of zoospore-like cells in certain chytrids 

 the primitive type of sexuality from which the heterogamic 

 copulation existing in the Monoblepharidales has arisen. This 

 second point of view receives support from the recent work of 

 Kniep on Allotnyces javanicus (p. 132) and from the fact that the 

 oosphere of Monoblepharis is characterized to a limited degree 

 by motility. 



The existence of this remarkable and interesting group of 

 aquatic fungi was first noted by Cornu (1871 : 58) . He (1872 : 82) 

 founded the genus Monoblepharis describing and figuring two 

 species, M. sphaerica and M. polymorpha, and enumerating a 

 third, M. prolifera. The last named species was independently 

 described and figured by Reinsch (1876: 293) under the name, 

 Saprolegnia siliquaeformis, only the sporangial stage being seen. 

 Cornu (1877: 227) regarded the species as identical with his 

 M. prolifera, and stated that since the publication of his earlier 

 paper he had observed its oospores. He says that these are 

 borne in oogonia resembling the zoosporangia, and result from 

 fertilization of an oosphere by motile spermatozoids. On the 

 basis of this statement and because of the uniciliate character 

 of the zoospores the species has been retained in the group by 



138 



