xli Description of the Figures. 



Fir. 



yi. Biplanes^ saj/rolcgrioidoi, zoosporangium formed from 

 the terminal hrancli of a filament ; a, the aperture 

 throu^'h \vluch most of the zoogonidia have escaped, 

 250. (After Lietgeb.) 



92. Zoogonidia of same, X 250. 



93. Sexual reproductive organs of same; a, oogonium 



furnished with perforations and containing seven 

 oospores ; &, antheridium. 



94. Theraphora Trailii, spore-cluster, x 400. 



95. Single spore of same, x 1200. 



9G. Uxtilago grammica, on stem of Glyceria Jluitans, nat. 

 size. . 



97. Spores of same, x 400. 



98. Empu^a muscae, gonidiophores and gonidia in various 



stages of develojiment ; a, gonidiophore ; h, gonidium, 

 X 200. 



99. Cj/sto/jus candidu^, showing the concatenate zoospo- 



rangia in various stages of development ; a, gonidio- 

 phore ; hj chains of zoosporangia ; X 400. 



100. Zoogonidium of same, X 750. 



101. Spliacelotheca hydrojnperu, longitudinal section tlirougli 



a sporophore of the fungus developed in the ovary of 

 Polygonum Injdropiper ; a, perianth ; &, wall of the 

 ovary ; c, spore-receptacle of the fungus composed of 

 hyplue ; d, columella ; e, spore-mass ; slightly X . 

 CAfter De Bary.) 



102. Dityuchasmonosporus, zoosporangium ; the reticulation 



is due to the numerous empty cellulose walls origin- 

 ally enclosing the zoogonidia which remain in the 

 zoosporangium ; to the left of the zoosporangium is 

 seen a free zoogonidium with its two cilia, x 250 



103. Oogonium of same containing a single oospore, X 400. 

 lU4. Oogonium of same clasped by an antheridium, x 400. 



(After Lietgeb.) 



Plate VI. 



105. Aphanomyces stellatus, fertile tip of a hypha converted 

 into a zoosporangium, showing the single row of 

 zoogonidia in the act of formation, x 400. 



