(DOGONIACER. 169 
Size. Cells: fem. -02-027 mm. 3-5 or 8 times as long ; 
oogonia ‘055-°057 x ‘075-08 mm.; oospore ‘049-051 x 
065-069 mm. 
Kirch. Alg. Schles. p. 58. Archer in Quart. Journ. Micr. 
Sci. 1866, p. 69. 
Gdogonium gemelliparum, Pringsh, Beitr. p. 71. 
Treland. 
Plate LXIV, fig. 2. Cdogonium Landsboroughii, variety gemelli- 
parum, with oogonium x 400. . 
C2:dogonium rivulare (Le Clerc). Braun, Chytr. p. 23, t. 1, f. 1-10. 
Oogonia single, or 2-7 continuous, obversely egg-shaped, 
opening by a pore above the middle; oospores obversely egg- 
shaped, rarely ellipsoid or nearly globose, not by a long way 
filling the oogonia; male plants a little slenderer than the 
female ; spermogonia 8-9 celled; spermatozoids binate. 
Size. Cells: fem. :045--045 mm. 38-8 times as long; cells: 
male :03-'036 mm. 4 times as long; oogonia ‘07-'085 x ‘13-16 
mm.; oospore ‘055-07 x :065-"1 mm.; sperm. cell ‘021-:028 x 
°014--016 mm. 
Wittr. Mon. Cidog. p. 86. Kirch. Alg. Schles. p. 58. 
Rabh, Alg. Eur. iii. 850 in part. 
Prolifera rivularis, Le Clere Prolif. 472, t. 28, f. 1. 
Scotland. 
Plate LXIV fig. 3. Cidogonium rivulare, with oogonium and oospore 
x 400. 
Species of which the organs of fructification are imperfectly 
known. 
a. Oospores globose or sub-globose. 
Gidogonium delicatulum. Kutz. Tad. ut, t. 33, f. 3. 
Pallid, basal cell scarcely lobed at the base, affixed, cells 
cylindrical; oogonia subglobose, inflated, a little extended at 
either pole ; oospore perfectly globose. 
Size. Cells :005-006 mm., 3 times aslong ; oogonia ‘02 x 
‘017 mm. ; ovspores °012--014 mm. 
Rabh. Alg. Eur. 355. Rabh. Alg. Ex. No. 1156. 
Deeside (Scotland). 
Plate LXVI. fig. 7. Cdogonium delicatulum, with oogonia x 400. 
CGdogonium tenellum. Kutz. Tad, 111, t. 33, f. 9. 
Basal cell two to three lobed, at first fixed, terminal joint 
obtuse, cells cylindrical or rather clavate; oogonia very much 
inflated; oospore globose, bright orange. : 
