BTJLBOCHAETE. 95 



OEDOGONIUM GRANDE, Kg. 



Oogonia oval, elliptic, considerably longer than wide ; 

 oospores oval, elliptic, filling the oogonia ; terminal cell 

 obtuse. 



Diameter veg. cells, 25-30 ^. ; 3-5 times longer. 

 Diameter oogon., 50-55 /< by 75-80 /*. 

 Diameter oospor., 45-50 /* by 68-72 //. 

 Meadow pools, Pennsylvania. 



Plate LXXVI, fig. 1, filament with oogonium, and two 

 zoospores having passed out through a fissure in the side of 

 cell, remaining attached. 



OEDOGONIUM PYRIFORME, Wittr. 



/ 



Monoecious, oogonium single, pear-shaped ; spermogonia 

 2-3 celled, subepigyiious or hypogynous. 



Diameter veg. cells, 13-14 // ; 826 times longer. 

 Diameter oogon. , 40-42 jn by 54-60 yu. 

 Diameter oospor. , 35-36 /* by 45-48 //. 

 Diameter sperm, cells, 10-12 ^ by 5-6 yu. 



Branchville, New Jersey. 



Plate LXXVII, figs. 11, 12, 13, filaments with oogonia and 

 spermogonia. 



OEDOGONIUM LONGATUM, Kg. 



Oogonia single (often solitary, terminal) rarely 2-3 con- 

 tinuous, ellipsoid, opening by an operculum, with a narrow 

 fissure ; oospores globosely-ellipsoid, scarcely filling the 

 oogonia ; terminal cell obtuse. 



Diameter veg. cells, 5-6 fji ; 2-3 times longer. 

 Diameter oogon., 16-17 }*. by 21-24 jn. 

 Diameter oospor., 15-16 yw by 17-19 //. 



Stagnant waters, far and near. 

 Plate LXXY, fig. 3, four short filaments. 



Genus 11, BTJLBOCHAETE, Ag. 



Filamentous plants, much branched ; terminal articulations, 

 and almost all others thickened upward and bearing at or near 

 the apex a long, thin, hyaline seta, bulbous at the base ; cell 

 membrane often punctate ; reproduction sexual as in Oedogonium; 

 oogonia opening by a lateral pore above the middle. Nearly all 

 of our species are dioecious. 



