(EDOGONIACEJS. 165 



Ireland, Scotland. 



Of these two species with echinulate oospores, the spines of the 

 former are broader at the base and conical, whilst in this they are slender, 

 and but slightly thickened downwards. 



Plate LX1I. fig. 2. (Edogonium echinospermum, with oogonia and 

 echinulate oospores x 400. 



SUB-SECTION u. Dioecious, with elongated male plants. 

 Oogonia, not, or scarcely, swollen. 



(Edogonium capillare. (Lin.) Kutz. Phyc. Gen. 225, t. 12, 



/. 1-10. 



Oogonia single, not swollen, cylindrical, opening by a pore 

 above the middle; oospores globose or cylindrical-globose 

 (somewhat quadrangular in longitudinal section) not filling the 

 oogonia ; male plants the same or almost the thickness of the 

 female plants ; spermogonia 1-4 celled, alternate with the 

 vegetative cells : spermatozoids binate. 



SIZE. Cells -OSS-'OSo mm., equal or twice as long; oogonia 

 1^ times as long ; oospore '03-*052 x '039-'063 mm. ; sperni. 

 cell -03--048 x -005--OQ6 mm. 



Kirch. Alg. Schles. p. 56. Rabh. Alg. Eur. N T o. 1180, 1417. 

 Wittr. Mon. (Edog. p. 30. 



Conferva capillaris, Linn. Spec. PI. 1636. 



CEdogonium regulare, Vaup. Beitr. (Edog. p. 213, t. 1, f. 

 1-10, not the Vesiculijera capillaris of Hassall. 



Britain. 

 Plate LX1I. Jig. 3. (Edogonium capillare, with oogonia x 400. 



b. Oospores manifestly swollen, 

 aa. Oospores globose, or nearly so. 

 (Edogonium calcaxeum. Cleve in Wittr. Disp. (Edog. p. 135. 



Oogonia single (very rarely twin), depressedly globose, 

 opening by a pore at the middle ; oospores filling the oogonia, 

 male plants the same, or almost the same, thickness as the 

 female; spermogonia 2-5 celled; spermatozoids single (?). 



SIZE. Cells > 011- < 014 mm., 2-4 times as long; oogonia 

 027--03 x -021--023 mm. ; oospores -026--028 x -02--021 

 mm. ; sperm, cell 'Ol-'Oll x -009--012 mm. 



Wittr. Mon. (Edog. p. 32. 



Vesiculifera compressa, Hass. F. W. Algas, 204, t. 53, f. 4. 



CEdogonium compresswn, Rabh. Alg. Eur. iii., 348. 



Britain. 



Specimens from the warm tank in the Victoria House, Kew Gardens, 

 had shorter cells than usual. It has apparently a tendency to become 

 more or less coated with a deposit of lime. 



