CHYTRIDIALES 573 



or irregular in contour, 2.7-5 \i in diameter and occasionally digitate 

 at the base. Resting spores smooth, light to medium brown, oval, sub- 

 spherical, 16 x 18 u, — 10 X 15 [x, spherical, 20 jjl, obpyriform, with a 

 1.75-2.5 \x thick wall and a large refractive globule usually surrounded 

 by several small ones; germination unknown" (Karling, he. cit.). 



Saprophytic in dead internodes of Chara coronata, Nitella flexilis, 

 and other algae, Karling (he. cit.; 1942c: 621) (?), United States. 



IMPERFECTLY KNOWN SPECIES OF EN DOCH YTRIUM 



? Endochytrium oophilum Sparrow 



Amer. J. Bot., 20: 72, text fig. 1 r-s. 1933 



Sporangium endobiotic, ovoid, 50 \x long by 30-35 \i wide, with a 

 short papilla which barely penetrates the wall of the egg and which 

 terminates in an operculum about 6 \x in diameter; zoospores spherical 

 or somewhat elongate, 3 [x in diameter, formed in the sporangium, pos- 

 teriorly uniflagellate, with a single globule, liberated with great rapidity 

 upon the dehiscence of the operculum ; resting spore not observed. 



Parasitic in rotifer eggs, United States. 



If further observations confirm that no vegetative system is ever 

 formed the fungus should be removed from Endochytrium and placed 

 in a new genus, which would be the operculate counterpart of Olpidium. 

 (See Karling, 1946b, pi. 2, fig. 46). 



NEPHROCHYTRIUM Karling 



Amer. J. Bot. 25:211. 1938 



(Fig. 34 F-H, p. 571) 



"Thallus intramatrical, monocentric, eucarpic. Zoosporangia var- 

 iously shaped, apophysate, with one or more exit papillae or tubes of 

 varying length; formed as an outgrowth from the apophysis and delimit- 

 ed from the latter by a cross wall at maturity. Rhizoidal system coarse, 

 richly branched, and extensive, with occasional elongate, spindle-shap- 

 ed, intercalary enlargements. Zoospores uniguttulate, posteriorly uni- 

 ciliate. Resting spores variously shaped, apophysate, thick-walled; form- 

 ed as an outgrowth from the apophysis; germination unknown" 

 (Karling, he. cit.). 



