LAGENIDIALES 937 



Olpidiopsis varians Shanor 



J. Elisha Mitchell Sci. Soc, 55: 171, text figs. A-E, pi. 24, figs. 1-13. 



1939 



(Fig. 75 D-F, p. 939) 



"Zoosporangia single to many, formed either in terminal or inter- 

 calary swellings of the host hypha, elliptical, oval, or spherical, extreme- 

 ly variable in size from 60 by 40 U. up to 350 by 140 \x, frequently about 

 200 by 80 u., walls giving cellulose reaction with chloroiodide of zinc, 

 smooth to very spiny, spines slender and somewhat conical, up to 7 u. 

 long, not giving the cellulose reaction; exit tubes commonly one to 

 three (as many as five have been observed). Zoospores oval to elongated, 

 3.8-4.6 u. long by 2.3-3.0 [X in diameter, usually about 4.2 by 2.8 \l, 

 biciliate, cilia of about equal length, measuring from about 4.2 to 4.6 \l. 

 Oogonia yellowish-brown and very variable in size, spherical, with 

 usually one but sometimes two antheridia attached, 26 to 83 u. in 

 diameter (not including spines), averaging between 52 and 61 [x ; exospore 

 wall colorless to yellowish, about 1.2 \x thick, bearing usually coarse 

 abruptly tapering spines which measure up to 8.6 [i long and have a 

 reticulum connecting them, not giving the cellulose reaction; endospore 

 wall yellowish-brown, about 1 .7 ;x thick, smooth, and giving the cellulose 

 reaction. Antheridia (companion cells) usually spherical, 17 to 30 \x in 

 diameter, commonly about 26 u., wall occasionally smooth but typically 

 covered by scattered spines similar to those on the oogonia but much 

 shorter, 1.7 \x at the longest, outer part of wall bearing spines usually 

 colorless, inner wall having a slightly yellowish cast. Contents of anther- 

 idia pass into oogonia and antheridia on mature oogonia are empty. 

 Germination takes place in this species by means of a germination tube 

 which usually penetrates the companion cell. Biciliate zoospores are 

 produced when the resting spore germinates" (Shanor, loc. cit.). 



On Achlya flagellata Coker, United States. 



Olpidiopsis spinosa Tokunaga 

 Trans. Sapporo Nat. Hist. Soc, 13 (1): 25, pi. 2, figs. 10-11. 1933 

 Sporangium ellipsoidal or cylindrical, mostly 92-198 \x long by 34-61 

 [jl broad, with from one to two discharge tubes; host hypha distended; 



