SPECIES OF ALG^. 

 II. KEY TO THE FRUITING PLANTS OF VAUCHERIA. 



49 



§ Antheridia slightly bent; the opening at top (a). 

 § " bent like a horn or hook (^). 



§ " not known (g). 



a. Oogonia nearly round (6). 



a. " not round; oval, often rather oblique (c). 



b. Oogonia about ioo/< in diameter .... dichotoma, 149 



b. " i25-i20;u " " Thuretii, 149 



c. Oogonia i-6, on one side, mouths lateral, produced beak-like, 



sericea, 150 



c. " erect, mouths not lateral, not produced beak-like, 



aversa, 149 



d. Antheridia beside or between the subsessile oogonia (1?). 



d. Antheridia terminal, with the oogonia on each side or lower 



down (/). 



e. Terrestrial, broadly expanded; antheridia bag-shape or clavate, 



Dillwynii, 150 

 e. Aquatic; antheridia short and straight, or elongate and variously 



curved . . . . . sessilis, 151 



/. Tetrestrial only; antheridium long, curved, oogonia on its back, 



terrestris, 153 

 /. Not strictly terrestrial; fruit on short lateral branchlets, 



geminata, 151 

 /. " " " fruit on short segments on the divided 



ends of branchlets ... . hamata, 152 



g. Branches regularly constricted at base and often elsewhere, 



tuber osa, 154 

 g. Branches not constricted; filaments i8o-2oo/< in diameter, 



pilus, 153 



One species 

 One species 

 One species 

 One species 



31. BOTRYDIUM. 



32. VOLVOX. 



33. EUDORINA. 



34. PANDORINA. 



granulatum, 155 



globator, 158 



stagnale, 160 



morum, 161 



