SPIROGYRA 169 



Dutch New Guinea, Hollandia (Robert Sigafoos Coll.), Biak (Britton 

 Coll.). 



In the Biak collection several instances of scalariform conjugation were 

 found. See also Number 72. 



70. Spirogyra submarina (Collins) Transeau 1915. Ohio Jour. 



Sci. 16, p, 25. Collins. 1909. Green Algae of North Amer- 

 ica, p. no. 



Vegetative cells 21-32 a*- x 6'^-iy'^iJi, with plane end walls; 2 to 3 

 chromatophores, making 1.5 to 3 turns; conjugation scalariform; tubes 

 formed by both gametangia; fertile cells enlarged; zygospores ellipsoid, 

 31-37 /tt X 56-120 /a; median spore wall yellowish-brown, smooth. 



United States: Massachusetts; Connecticut. 



Bermuda; China, Peiping and Nanking (Li Coll.). 



71. Spirogyra rivularis (Hassall) Rabenhorst 1868. Flora Eu- 



ropaea Algarum. 3, p. 243. 



Vegetative cells 36-41 ;«. x 100-400 /x, with plane end walls; 2 to 3 

 chromatophores, making 2.5 to 3.5 turns in the cells; conjugation scalar- 

 iform, rare; tubes formed by both gametangia; fertile cells shortened, 

 cylindric or enlarged; zygospores ellipsoid, 35-42 a^ x 60-100 /x; median 

 spore wall yellow or brownish-yellow, smooth. (PI. XXVI, Fig. 8.) 



United States: Kansas; Iowa; Michigan; Alabama; Kentucky. 



Widely distributed in Europe, South Africa, New Guinea, and several 

 provinces of China. 



Most of the early records of this species are based on vegetative material. 

 It is said to occur in running water, attached to submerged objects. In the 

 vegetative condition it certainly cannot be distinguished from S. decimina, 

 which in America is also frequently attached and floating in small streams. 

 See note under S. turfosa (No. 79). 



72. Spirogyra biformis Jao 1935. Sinensia. 6, pp. 594-95, PI. 6, 



Fig. 66. 



Vegetative cells 38-48/t x 64-i5o(-i9o) /i, with plane end walls; 

 chromatophores (i-)2-3, making 1.5 to 4.5 turns; conjugation usually 

 lateral, rarely scalariform; tubes formed by both gametangia; fertile 

 cells cylindric or slightly enlarged, sometimes shortened to 38 /x; sterile 

 cells some times swollen to 58 /x in diameter; zygospores ellipsoid with 

 rounded ends, 36-51 ^u. x 60-83^",; median spore wall yellow, smooth. 

 (PI. XXVI, Figs. 9-10.) 



China, Szechwan; New Guinea (Robert Sigafoos Coll.); Philippines, 

 Leyte (Britton Coll.); Brazil (Drouet Coll.). Compare with Number 69. 



In the collection from Leyte conjugation is scalariform, elsewhere lat- 

 eral. In one of the collections from Leyte a few cells have 4 chromatophores. 



