Protoachiya paradoxa

Protoachiya paradoxa (Coker) Coker, Saproleg. 91. 1923
Achlya paradoxa Coker, Mycologia 6: 285. 1914.
Isoachlya paradoxa C. H. Kauffraan, Am. Jour. Bot. 8: 231. 1921.
Plant delicate; hyphae straight, slender, little branched, the larger ones about 37 x thick below, the average being about 10-15 n; sporangia plentiful at all stages, narrowly clavate, largest at the distal end, there about 20-30 ^ thick, rounded at the tip, furnished with a distinct but short papilla; secondary sporangia formed usually by cymose branching beneath the old ones, but occasionally also by proliferation through the empty ones as in Saprolegnia except that the new sporangia are formed entirely outside the old ones; dictyosporangia not rare; spores diplanetic, on emerging all ciliated, but varying greatly in behavior — some swimming away as a rule, others remaining attached in an irregular group to the tip of the sporangium; oogonia produced on the tips of short lateral branches, usually near the base of the main hyphae, sometimes intercalary, spheric, 32-80/* in diameter (one seen 100 fx), sometimes elongate or flask-shaped especially when intercalary, the walls smooth and usually with a few pits; eggs centric, usually 2 or 4, often 6, rarely 1 to 12, 22-37 n in diameter, averaging about 30^; antheridia always present, generally several, sometimes so numerous as to completely cover the oogonia, short, clavate, or often tuberiform and branched, terminating slender branches of diclinous or rarely androgynous origin which at times show a tendency to twine about the oogonial branches; antheridial tubes entering the oogonia, running among the eggs, and probaably fertilizing them.
Type locality: Chapel Hill, North Carolina.
Habitat: Fresh water and mud.
Distribution: Wisconsin and North Carolina; also in Europe.