CEDOGONIUM. 81 



b. Oospores ellipsoid or egg-shaped. 



OEDOGONIUM BORISIANUM, (Led.) Wittr. 



Gynandrosporous ; oogonia single, or in series of 2-4, 

 obversely egg-shaped, opening by a pore above the middle 5 

 oospore obversely egg-shaped or subglobose, almost filling 

 the oogonium ; supporting cells swollen and usually curved 5 

 aiidrosporangia 2-5 celled ; terminal cells obtuse ; dwarf 

 males slightly curved, seated on the supporting cells ; sper- 

 mogonia cells single or twin. Very variable in size. 



Diameter veg. cells, 15-33 JJL ; 3-5 times longer. 

 Diameter supporting cells, 31-40 ^ ; 2 times longer. 

 Diameter oogon., 45-50 ^ by 60-75 ju. 

 Diameter oospor. , 40-60 ja by 40-80 yw. 

 Diameter androsp. cells, .17-20 ^ by 10-12 /*. 

 Diameter stipe dwarf male, 15-18 /* by 45-80 /*. 

 Diameter sperm, cells, 8-10 // by 12-20 //. 



Syn. Prolifera Borisiana, Led. ; Oe. apophysatum, A. Br. ; Oe. 

 setigerum, Vaup. ; Oe. miraMle, Wood. 



Ur. Wood says of this species (mirabile) that its oogonia 

 have two pores of fecundation. But this statement, suggests 

 Dr. Wittrock, is based on a misconception of facts as may 

 be seen by Wood's own figures. No form of Oedogonium 

 has more than one pore of fecundation on a single oogonium. 







Frequent, and widely spread ; very variable in size, but 

 readily distinguished by the large and more or less bent, 

 supporting cells. Have made several slight changes in the 

 diagnosis of the European plant to adapt it to our forms. 



Plate LXXVIII, fig. 6, an undeveloped oogonium ; fig. 7, 

 a smaller form ; fig. 8, a large form ; fig. 9, the more fre- 

 quent form. 



OEDOGONIUM CONCATENATUM, (Hass. ) Wittr. 



Gynandrosporous, oogonia 2-6 seriate, or single, egg- 

 shaped or quadrangularly ellipsoid, opening by a pore above 

 the middle ; oospore nearly filling the oogonium ; sporoderm 

 delicately porose ; supporting cell somewhat swollen : andro- 

 sporangia 2-6 celled ; terminal cell obtuse ; dwarf males 

 moderately curved, seated on the supporting cells ; spermo- 

 gonia two-celled. 



Diameter veg. cells, 25-40 ^ ; 3-6 times longer. 

 Diameter oogon., 70-83 n by 90-105 yw. 

 Diameter oospor., 65-76 IJL by 85-95 yw. 



