668 AQUATIC PHYCOMYCETES 



BLASTOCLADIOPSIS Sparrow 



J. Wash. Acad. Sci., 40: 52, 1950 

 (Fig. 47 G-J, p. 682) 



Thallus filamentous, without a well-defined basal cell, nonseptate 

 except where reproductive organs are delimited, dichotomously or sub- 

 dichotomously branched; anchored to the substratum by a system of 

 coarse-branched rhizoids; zoosporangia irregular or somewhat cylin- 

 drical, with one to six discharge papillae; zoospores posteriorly uni- 

 flagellate, with several oil globules and a conspicuous nuclear cap; 

 resting spores usually spherical or somewhat ellipsoidal, with a thin, 

 golden to amber-colored, smooth nonpunctate wall, borne singly and 

 loosely within their container, upon germination cracking open to dis- 

 charge posteriorly uniflagellate zoospores through one or more pores; 

 gametophyte unknown. 



So far as known, a monotypic genus, in soil. 



Blastocladiopsis parva (Whiffen) Sparrow 



J. Wash. Acad. Sci., 40: 53, figs. 27-30. 1950 

 Blastocladia parva Whiffen, J. Elisha Mitchell Sci. Soc, 59: 40, pi. 4, figs. 

 17-36. 1943. 



Thallus 300 u, or more in length, unbranched or more commonly 

 dichotomously or subdichotomously branched; hyphae 12-50 u. in 

 diameter, somewhat irregular; zoosporangia rare, terminal on the hy- 

 phae, irregular or somewhat cylindrical, 40 by 65.6 to 41.3 by 90.2 \l, 

 with one to six discharge papillae; resting spore lying loosely in a 

 smooth-walled or occasionally apically papillate container, spherical, 

 ellipsoidal or ovoid, 36.8 by 41 jj. to 35.2 by 77.1 jj., with a golden to pale 

 amber-colored smooth, nonpunctate wall, upon germination the wall 

 cracking open and posteriorly uniflagellate zoospores escaping through 

 one or two discharge pores. 



Saprophytic in soil, coll. J. N. and P. Couch, Whiffen (1943), United 

 States; on snake skin, grass used as bait, in soil, Sparrow (1950), Cuba. 



The measurements are those for Whiffen's Texan material. In the 

 Cuban fungi, the zoosporangia, also very rarely formed, ranged from 

 55 to 70 (x long by 22 to 25 u. broad. They developed a lateral as well as 



