CHYTRIDIALES 145 



(1933b: 79, pi. 5, figs. 4-7), Japan; Sparrow (1936a: 427, pi. 14, figs. 

 2-4), Great Britain; Petersen (1910: 554), Sparrow (he. cit.), Den- 

 mark; Karling (1941b: 108 [? adults]; 1948c: 508), rotifer eggs (?), 

 Sparrow and Barr (1955: 554), United States; Berczi (1940: 79, pi. 

 2, fig. 1), Hungary. 



The shape of the sporangium, as in other endobiotic chytrids, 

 undergoes considerable modification when more than one fungus is 

 present within the limited confines of the substratum. Here, the spo- 

 rangia often tend to be smaller and to lose their regular ellipsoidal 

 or spherical shape and become irregular and saclike. 



Zoospores of an undescribed parasite of rotifer eggs "near O. 

 gregarium" are described by Scherffel (1925a: 66, pi. 5, fig. 222). 

 They differ from those of the present species in containing several 

 globules rather than one. Both Butler and Sparrow noted that the 

 resting spores sometimes lie loosely in a surrounding membrane. Butler 

 suggested that this had come about because the fungus gained entrance 

 after segmentation of the animal embryo had occurred. Since some of 

 the sporangia in his material were similarly placed, this seems plausible. 

 It is also possible that the spores arise by contraction and subsequent 

 walling of their protoplasm, as in some species of Pythium. 



The protoplasm of the eggs attacked by Nowakowski's fungus was 

 pinkish and the thallus of the chytrid was similarly colored. The zoo- 

 spores, however, appeared to be colorless. From the remarks of Fischer 

 (1892: 31), it is probable that he observed the fungus, but the host 

 is not given. 



Olpidium granulatum Karling 

 Lloydia, 9: 3, pi. 1, figs. 1-18. 1946 



"Sporangia, hyaline, smooth, oval, ellipsoid, 7-26 12—44 jjl, usu- 

 ally numerous, up to 16 in a cell, subspherical, 8-50 [x diam., with 

 one, 3.5-5 (j. wide by 6-10 \i long, exit tube which usually does not 

 extend far beyond the surface of the host cell. Emerged zoospores 

 forming a globular mass at the exit orifice before dispersing; spherical, 

 3.5-4.5 [x, with numerous minute granules and a 38-45 \i long flagel- 

 lum. Resting spores hyaline, smooth, spherical or oval, 14-22 jj.; ger- 

 mination unknown" (Karling, he. cit.). 



Parasitic in rotifer eggs, Brazil. 



