THE FLORA OF M 1.1; \£E \. \~ 



Spirogyra variant (Hass.) Kubtz. 1. c, 439. 



Zygnema varians II \ss. 1. c, 118. 



Vegetative cells 25 35 fi in diam., 2 3 times as Long, spiral Bingle, making 1'. 

 turns in each cell, margins dentate; zygogoninm muofa swollen mi, the 

 conjugating side, straight on the other Bide; zygospore oval or elliptical 



33-38 // in diam., 1^2-2 times as long as wide. 

 Creeks, Lincoln. PI. VIII., Figs. 7 and 7 a. 



Spirogyra porticalis (Muell., Cleve Svonsk Zygnem. 22. is.;:;. 

 Conferva porticalis Muell. Nov. Act. Petrop. Ill, 90. 1785. 



Filaments very gelatinous; vegetative cells 30 is ,. in diam.,2 6 times as long; 

 spirals 1, rarely 2, making 15 1 turns in each cell; zygogoninm inflated; v.y 

 gospore globose-ovate, yellowish at maturity, 42 // in diam.. once to twice 

 as long. 

 Lincoln. PI. X., Figs. 5 and 5 a. 



B. Two or more spirals in each cell. 



Spirogyra decimina (Muell.) Kcetz. Phyc. Germ. 223. 1815. 

 Conferva decimina Mlell. Nov. Act. Petrop. III., 22, f. 3. 1785. 



Vegetative cells 34-40 /i in diam., 2-4 times longer than broad; 2 rarely 'i large 

 spirals in each cell, making 1-2 turns; zygogonium not inflated; 

 spore oval or globose, 33-44 /i in diam. 

 Ponds, Lincoln. PI. IX., Fig. 1, a, b. 



Spirogyra fluviatilis Hilse in Rabh. Fl. Eur. Alg. III.. 213. 1868. 



Vegetative cells 34-38 // in diam., 5 times as long; spirals 1. .lark 



making 3^-2^ turns; zygogonium much indited; zygospore oval, 55 - 

 Lincoln. PI. X, Figs. 1 and 1 a. 



Spirogyra majiiMcnla Kttetz. Sp. Alg. 411. 1849. 



Vegetative cells 54-62 // in diam., 2-10 times as long; chlorophyll Land- .; 9, 



light green, usually lax; zygogonium not inflated, 2-1 tines Long* r than 



wide; zygospore oval, 72x50 //. 

 Common in streams. PI. X., Figs. 3 and 3 a. 



Spirogyra adnata E^uetz. 1. c. 



Vegetative cells 40-45 // in diam., 1 3 times as long; spirals 2 "> in eaofa cell, 

 making 3-4 turns; zygogonium moderately swollen; zygospore ..val t<> 

 elliptical. 



Lincoln. PI. X., Figs. 4 and 1 a. 



Spirogyra orbicularis (Hass.) Kuetz. 1. «■. 112. 



Zygnema orbiculare Hass. Brit, P. W. Alg. 138. 1845. 



Vegetative cells 118-138 ft in diam., a little longer than I. road; bands 



margins finely notched, each describing ' . to ■, turn in a cell; zygogoninm 

 not inflated; zygospore lenticular, brown at maturity, L02x84 . 



Lincoln. PI. X.. Figs. 2 and 2 a. 



Spirogyra craswa Kcetz. Phyc. Gener. 280. L843. 



Vegetative cells 150 150 «in diam.. 1 l 1 ,. times as long; bands anmerons, den 

 ticulate or tuberculate, making % to 1 turn or more in each cell, 

 gonium uot inflated; zygospore broadly oval, elliptical, or ovoid, 144x1 



Lincoln, South Bend, common, l'l. XL Fig-. 1 and 1 a. 



