376 AQUATIC PHYCOMYCETES 



a flagellum 20-24 jx long, upon emergence forming a globose mass 

 before assuming individual motility; rhizoidal system arising for the 

 most part from one place on the base of the sporangium, coarse, much 

 branched, 100-600 u. in length, sometimes penetrating more than one 

 cell of substratum, main axes 3-7 u. in diameter; resting spores mostly 

 spherical and 18-24 [x in diameter, oblong, 10-13 by 15-18 [x, elongate 

 and truncate, 10-22 [i, with one to three large centric globules 8-15 [x 

 in diameter, golden-red or rust-colored, wall rust-colored, smooth, 1.5-2 

 u, thick, germinating by a pore to form a zoosporangium. 



Saprophytic in dead leaves of Elodea canadensis, Eriocaulon septan- 

 gulare, and Vallisneria sp., United States. 



Only the Latin description of this species, unaccompanied by figures, 

 has been published. No comparison was made by its author with 

 Entophlyctis rhizina with which, from Schenk's figures, it may be 

 identical. 



Entophlyctis pygmaea (Serbinow) Sparrow 

 Aquatic Phycomycetes, p. 256. 1943 



Catenaria pygmaea Serbinow, Scripta Bot. Horti Univ. Imper. Petro., 

 24: 161, pi. 3, figs. 1-15. 1907. 



Sporangium endobiotic, single, subspherical or long-cylindrical with 

 rounded ends, 17-26 \i long by 6-12 u, in diameter, terminal or intercalary, 

 separated by cross walls from the rhizoidal system, with a single short pa- 

 pilla which penetrates the wall of the substratum ; rhizoidal system strong- 

 ly dichotomously branched, polyphagous, the main axis arising from one 

 or opposite ends of the sporangium, broad and tubular, up to 3 ;x in 

 diameter, the branches rhizoidal; zoospores spherical, 1.5 u, in diameter, 

 with a single globule, posteriorly uniflagellate, emerging upon the 

 deliquescence of the papilla and forming a temporary compact motion- 

 less mass at the orifice before assuming motility; resting spore borne 

 like the sporangium, spherical, with a thickened colorless wall and a 

 central oil globule, germination not observed. 



Parasitic in Mougeotia sp., Serbinow (loc. cit.), Finland; saprophytic 

 in Mougeotia, Sparrow (1943:257), United States; Mougeotia sp. y 

 Litvinow (as Catenaria pygmaea) (1953: 84), Latvia. 



The thallus of this organism is definitely monocentric and, so far as 

 could be determined, the sporangium is inoperculate. 



