— 159 — 



Var. vulgare Wittr. in Nov. Acta Reg. Soc. Scient. Upsala, 1. c. 



Grass, cell, veget. 5 — 7,5//; altit. 3 — 5-plo major; 

 „ oogon. 19-20/,; „ 18-23/,; 

 „ oospor. 17,5— 18,5 /, ; „ 13 — 14/,. 



In stagnant water in riverbed. 



Area: Europe, N. America and New Zealand. 



3. Ol. maximum West & G. S. West, n. sp. (Tab. nostr. IV, fig. 39 

 -4L) 



Œ. dioicum, macrandrium ; oogoniis singulis, subquadratis vel 

 oblongo-rectangularibus, levissime tumidis; oosporis oogonia exacte 

 complentibus, subquadratis vel oblongo-rectangularibus, in sectione 

 optica verticali circularibus ; membrana oosporæ crassa, glabra, 

 quasi crassescione membranæ oogonii formata; plantis masculis 

 eadem crassitudine ac femineis; antheridiis pluricellularibus (?). 



Crass, cell, veget. 89 — 93/,; altit. IV2 — 2 (usque ad 3) -plo major; 

 „ oogon. (et oospor.) 105 — 107/,; altit. 115 — 136/,; 

 „ cell, antherid. 77 — 86/,; altit. 7 — 15/*. 



A large quantity of this Œdogonium was seen from stagnant water 

 and the plants were in abundant fruit. The oospores are rather remar- 

 kable being somewhat rectangular in outline, and having a w T all which is 

 apparently formed by an increase in thickness of the wall of the oogonium. 

 Thus, when the spore is ripe there is no differentiation between the oospore 

 and the oogonium, and the ripe oospores are set free by the breaking up 

 of the filaments. Only one example of the antheridia was observed and 

 this was only a fragment. From its general appearance it is highly pro- 

 bable that the antheridia are many-celled, but this point could not be 

 definitely determined. 



It may be compared with Œ. fiibulosum Hirn from w r hich it is 

 easily distinguished by its larger size and its differently shaped oospores, 

 which completely fill the oogonia. 



4. CK. dioicum Garter in Ann. Mag. Nat. Hist. I, no. 4, 1858, p. 30, 

 t. Ill, f. 1, 2, 5-8, 13-16; Hirn in Acta Soc. Scient. Fennicæ, Tom. XXVII, 

 no. 1, 190, p. 175, t. XXVIII, f. 163. (Tab. nostr. IV, fig. 42.) 



Grass, cell, veget. 31 — 35/«; altit. 3 — 5-plo major; 

 oogon. 97/,; „ 100/,; 



„ oospor. 70/,; „ 70/,. 



We place this plant under Œ. dioicum Garter owing to the relative 

 size of the filaments and the peculiar oogonia, which the oospores do 

 not fill. It agrees with Garter's species in everything except the length 

 -of the cells, which are proportionately a little longer. 



In stagnant water in the jungle, among the preceding species. 

 Area: India. 



Botanisk Tidsskrift. 24. Bind. 



11 



