734 AQUATIC PHYCOMYCETES 



basal portions attain a diameter of 12-15 \l, tapering distally to 1.5-2 u.; 

 sporangia narrowly cylindrical, rarely somewhat irregular, 130-234 u, in 

 length by 10.4-13 u. in diameter, occurring singly, terminally, or occa- 

 sionally in clusters sympodially arranged; zoospores 10.4-13 u. in length 

 by 7.8-10.4 [ji in diameter; oogonia in young material broadly to 

 narrowly pyriform, in older plants differing somewhat in shape, the 

 even contour often being notched at the point of insertion of the an- 

 theridium, variable in size, usually 20-28 \l long by 20-28 jx tapering 

 proximally to 5-7 u, in diameter; antheridia epigynous but often in a 

 series of incompletely developed sex organs appearing hypogynous, 

 when terminal, somewhat cylindrical, when intercalary, somewhat 

 geniculate with a broadly conical apex, varying greatly in size, usually 

 about 10-35 u, in length by 5-10 u. in diameter; antherozoids from five 

 to seven, each about 5.2 \x in length by 2.6 \x in diameter; oospores 

 spherical, nearly always exogenous, with a thick brown wall beset with 

 bullations 1.5-2 \x in height, or oftentimes with light-colored undula- 

 tions, 12-25 \x in diameter; oospore germinating by means of a hypha. 



Saprophytic on submerged twigs of various types and on animal 

 remains. Cornu (loc. cit.), France; Lagerheim (loc. cit.), Sweden; 

 Woronin (1904), Finland; Tiesenhausen (1912: 265, fig. 1), Switzer- 

 land; Petersen (1909:400; 1910:535, fig. 15 a-b), Lund (1934:46, 

 fig. 22d), Sparrow, Denmark; Claussen (1912), Minden (1902:806), 

 Laibach (1927:601, fig. 2), Germany; Apinis (1930:237), Latvia; 

 Wettstein (1921), Austria: Thaxter (F.), Sparrow (S.) (1933b: 529, 

 fig. 1 a-m, r, text fig. 2 a-k, pi. 20, figs. 7-13, 19-20, 28 [this species?], 

 36, 38-39; 1933c: 530), twigs, Wolf (1944: 18), Beneke (1948: 30), R. 

 M. Johns (comm.), (North Carolina) Betula twigs, Sparrow and 

 Barr (1955: 555), United States; Barnes and Melville (1932: fig. Ill, 

 3), twigs of Quercus robur, Fraxinus excelsior, Perrott (1955: 278, pi. 

 12, figs. 1-3. text-figs. 15 c-h. 17), Great Britain; Pyrus pashia twig, 

 Shen and Siang (1948: 189, fig. 7), China. 



Monoblepharis brachyandra is said to be distinct from M. polymorpha 

 chiefly in the uneven contour of the oogonium at the place of insertion 

 of the shorter stouter antheridium and in the frequently intercalary 

 position of the latter, or, when epigynous, its tendency to be formed on 

 the lower third of the oogonium. The oospores differ in being smaller 



