CHYTRIDIALES 333 



Chytridium lagenaria Schenk, pro parte, Verhandl. Phys.-Med. Gesell. 

 Wurzburg, A. F., 8:241, pi. 5, figs. 12, 14-15. 1858. Non C. lagenaria 

 Schenk, Ueber das Vorkommen contractiler Zellen im Pflanzenreiche, p. 

 5. Wurzburg, 1858. 



Sporangium sessile, subspherical, or ovoid, with a blunt rounded 

 apex, 7.8-20 u, in diameter (see discussion below), wall somewhat 

 thickened, smooth, colorless, not giving a cellulose reaction; rhizoids 

 unbranched or branched, arising from a single basal stalk or from 

 several places on a subsporangial broadly expanded and flattened 

 (5.2-15.6 (jl wide by 5.2-1 1.2 \l high) or spherical apophysis; zoospores 

 ovoid, 2-5.2 \x in diameter, with a colorless eccentric globule and a 

 long flagellum, emerging through a broad apical pore; resting spore 

 not observed. 



On Zygnema sp., Spirogyra crassa, Oedogonium sp., Schenk (1858a), 

 Germany; Spirogyra sp., Domjan (loc. cit.), Hungary. 



The sizes given in the Hungarian portion of Domjan's paper are 

 as follows: sporangia, 7.8-15.6 u. wide by 7.8-1 5.6 \i high; apophysis, 

 5.2-15.6 (j. wide by 5.2-1 1.25 \x high; zoospores, 5.2 u, in diameter. 

 The last measurement is more than twice that given by Schenk (2 u.). 

 Since only the diameter of the sporangium is given by Schenk, Dom- 

 jan's figures on its height have not been included in the diagnosis. 



From both Schenk's and Domjan's accounts, the apophysis often 

 equals and even exceeds the diameter of the sporangium. Schenk 

 observed that zoospores were formed in the apophysis as well as in 

 the sporangium. 



The separation of the inoperculate form first observed by Schenk 

 from the operculate Chytridium lagenaria (p. 522), which he found 

 soon after, has been suggested before (Sparrow, 1936a: 437), and 

 Domjan's placing of the fungus in Phlyctochytrium appears wholly 

 justifiable. 



Phlyctochytrium chaetophorae de Wildeman 

 Bull. Soc. Roy. Bot. Belg. (Mem.), 35: 46. 1896 

 Rhizidium chaetophorae de Wildeman, La Notarisia, 10 (3): 35. 1895; Ann. 

 Soc. Beige Micro. (Mem.), 19: 217, pi. 7, figs. 15-21. 1895. 



Sporangium sessile or on a slender stalk, narrowly obpyriform, 



