90 FRESH-WATEU ALG^ OF THE UNITED STATES. 



OEDOGONIUM CARDIACUM, (Hass.) Wittr. 



Oogonia single, between heart-shaped and globose, open- 

 ing by a pore a little above the middle ; oospores globose, 

 not filling the oogonia ; male plants a little slenderer than 

 the female ; spermogonia 2-10 celled ; spermatozoids binate, 

 terminal cells obtuse. 



Diameter veg. cells, fern. , 18-30 yw 2-7 times longer. 

 Diameter veg. cells, mas., 15-25 yw; 2-6 times longer. 

 Diameter oogon., 50-70 yu by 58-85 yw. 

 Diameter oospor., 42-60 yw by 42-60 yw. 

 Diameter sperm, cells, 15-21 yu by 10-13 yw. 



Syn. Oe. inequaUs, Wood ; Oe. pulchellum, Eab. 



In pools near Philadelphia, Pa. The description by Wood 

 is imperfect, nevertheless the plant appears to belong to 

 this species. 



OEDOGONITJM CARBON ICUM, Wittr. 



Oogonia single or twin, obovate, or ovate globose, opening 

 by a pore above the middle ; oospores ellipsoid-globose or 

 nearly globose, barely filling the oogoniuin ; male plants a 

 little more slender than the female ; spermogonia 2-5 celled ; 

 spermatozoids binate ; terminal cells obtuse. 



Diameter veg. cells, fern. , 16-30 yw ; 3-6 times longer. 

 Diameter veg. cells, mas. , 14-16 yw ; 3-6 times longer. 

 Diameter oogon., 43-52 /* by 50-72 /u. 

 Diameter oospor., 42-50 yw by 46-56 yw. 

 Diameter sperm, cells, 13-14 /t by 12-14 /u. 



The only specimens of this species identified were collected 

 in Iowa. 



Plate LXXXII, figs. 14, 15, male and female plants. 



OEDOGONIUM PRINGSHEIMII, Cram. 



Oogonia single or 2-6 seriate, sub-obovate-globose, open- 

 ing by an operculum, with a very narrow fissure ; oospore 

 globose, not distinctly filling the oogonium ; male plants 

 somewhat smaller than the female ; spermogonia 2-10 celled, 

 often alternate with vegetative cells towards the ends of fila- 

 ments ; terminal cells obtuse or shortly apiculate. 



Diameter veg. cells, 12-20 ^ 5 2-4 times longer. 



Diameter oogon., 30-43 V by 36-45 yw. 



Diameter oospor. , 28-35 /* by 28-34 yu. 



Diameter sperm, cells, 10-15 ^ by 6-9 yw. 



