CHYTRIDIALES 327 



Presumably this is one of the first chytrids seen by Braun, in 1846 

 (Braun, 1856a: 22). He describes the globules of the zoospores in the 

 sporangium as yellowish or greenish yellow, a feature not mentioned 

 by subsequent observers. Escape of the mature zoospores was ob- 

 served by both Frantzius and Bail. The formation by the host of a 

 protective plug of wall material at the point of entrance of the parasite 

 was noted by Braun. 



It is probable that further observations on this species will reveal 

 the presence of rhizoids. 



Phlyctochytrium proliferum Ingold 

 Trans. Brit. Mycol. Soc, 25: 45, fig. 1, pi. 4, fig. 1. 1941 



"Sporangium ovoid, 10-15 x 6-10 \x, with the longitudinal axis par- 

 allel to the surface of the host cell. Sporangium dehiscing by large 

 lateral pore. Zoospores spherical, 3 \x in diameter, uniguttulate. New 

 sporangia formed by a process of internal proliferation. Intramatrical 

 part spherical or sub-spherical, 3-5 \x in diameter. Resting spores spher- 

 ical or ovoid, 8 \x in diameter, smooth-walled, extramatrical, with a 

 single conspicuous oil drop" (Ingold, he. cit.). 



Parasitic on living Chlamydomonas, Great Britain. 



Ingold is of the opinion that the secondary sporangia of this species 

 develop as do those of Thraustochytrium (p. 830), that is, from a 

 portion of the protoplasm which does not take part in the original 

 cleavage of the zoospores. 



Phlyctochytrium japonicum (Kobayasi and Ookubo), comb. nov. 



Rhizophydiitm japonicum Kobayasi and Ookubo, Bull. Nat. Sci. Mus. 

 (Tokyo), 33:54, fig. 1. 1953. 



Zoosporangia scattered, elongated ellipsoidal, 12-25 [j. high, 5-10 jx 

 in diameter, thin-walled, smooth, colorless, at maturity forming a 

 broad apical discharge pore; rhizoidal system composed of a main 

 axis and rhizoids, the main axis expanded as a prolongation of the base 

 of the zoosporangium, clavate or tuberous, 3-10 by 2-5 \i, sometimes 

 lacking, rhizoids short, one to five arising from the base of the main 

 axis, simple or branched; zoospores globose or ellipsoid, 2.5-5 [i. 



