446 AQUATIC PHYCOMYCETES 



ical specimens 50-75 \x in diameter, the irregular ones 60-170 by 40-140 

 [x, contents with numerous orange-brown droplets; rhizoids arising at 

 from one to ten places on the sporangium, stout, up to 15.6 \i in diameter 

 near the point of origin, extensive, much branched, 500 u, or more in 

 length; zoospores up to several hundred in a sporangium, posteriorly 

 uniflagellate, emerging through a discharge tube up to 50 u, long by 20 

 [i. in diameter and forming a motionless globular cluster at the orifice 

 before dispersing, nearly spherical, 5.2 \i in diameter, with a minute 

 orange-brown globule and several refractive granules, movement swim- 

 ming or amoeboid; resting spore intercalary or rarely terminal, rela- 

 tively thick-walled, spherical, ellipsoidal, or irregular, with a densely 

 granular orange-brown content. 



In submerged empty larva cases of the Chironomidae, Odonata, 

 Sparrow {he. cit.)\ rotting oat leaves, Karling (1941b: 108), chitin 

 bait, from moist soil, Karling (1948c: 509), Karling (1941a: 387; 1942c: 

 621), cellophane bait, Sparrow (1952d:767), United States; soil, 

 Shanor (1944), Mexico; boiled maize leaf, Sparrow (1952a: 39), Cuba; 

 from soil, substrate?, Gaertner (1954b: 22), Egypt, Equatorial East 

 Africa, South Africa; boiled grass leaves, Sparrow (1957a: 528), 

 Great Britain. 



This is one of the largest and most striking species of the genus. The 

 developing thallus consists of a sporangial rudiment which, though it 

 is generally spherical, subspherical, or ellipsoidal, may occasionally be 

 irregularly peltate and appressed to the inner surface of the substratum. 



RECENTLY DESCRIBED TAXON \ - 



Rhizophlyctis harderi Uebelmesser 



Arch. f. Mikrobiol., 25: 324, fig. 7. 1956 



Sporangium spherical, smooth- walled, 40-60 u, in diameter; rhizoids 

 arising from one or several places on the sporangium, delicate, branched, 

 those within the substrate with a small apophysis; zoospores spherical, 

 4 [x in diameter, with a 20 u, long flagellum and small colorless basal 



1 Not included in the key. 



2 See also R. ingoldii in Sparrow (1957a). 



