92 ZYGOPHYCE. 
Plate XXXVI. fig. 1. a,sterile cells X 200; 8, conjugating cells with 
zygospores X 200; c, sterile cells of inflated form X 200; d, conjugating 
cells with zygospores xX 200; e, f, g, outlines of zygospores X 400. 
Spirogyra longata. Vauch. 
Sterile cells with the ends truncate, 3 to 8 times as long as 
broad, chlorophyll bands single or rarely two, making 12 to 
6 turns of a spiral. 
Spores 1} to 2 times as long as broad, membrane even, chest- 
nut colour. 
Sporiferous cells swollen and usually longer than the spore. 
Size. Cells 024-03 mm. diam. Zygospore -04-07 x -03 mm. 
Cleve Monog. Zygn. p. 20, t. 3, f. 8-10; t. 4, f. 1-7; t.10, 
f. 11-13. 
Conjugata longata, Vauch. Conf. p. 71, t. 6, f. 1. 
In pools and ditches. 
var.u. Communis. 
Sterile cells 3 to 8 times as long as broad. 
Spirogyra longata, Kutz. Tab. v. t. 20, f. 1. Rabh. iii. 238. 
Petit Spirogyra t. 5, f. 4, 5. 
Zygnema commune, Hass. Alg. t. 28, f.5, 6. Ann. Nat. Hist. 
x. (1842) p. 39. Jenner Fl. Tunb. Wells, 180. 
Zygnema estivum, Hass. Alg. t. 28,f. 3,4. Ann. Nat. Hist. 
xi. (1843), p. 433. Jenner Fl. Tunb. Wells, 180. 
Zygnema angulare, Hass. Alg. t. 34, f. 1, 2. Jenner FI. 
Tunb. Wells, 180. 
Zygnema angulatum, Hass. Ann. Nat. Hist. x. (1842) p. 41. 
Zygnema reversum, Hass. Alg. t. 33, f. 3. 
Zygnema alternatum, Hass. Alg. p. 154. 
Zygnema mirabile, Hass. Alg. t. 35, f. 1-3. 
Spirogyra communis, Kutz. Tab. v. t. 19, f. 4. Petit Spiro- 
gytat. v. f. 1-3. : 
Rhynchonema angulare, Kutz. Tab. v. t. 34, f. 1. Rabh. iii. 
232. 
Rhynchonema reversum, Kutz. Rabh. iii. 232. 
Spirogyra subtilis, Kutz. Tab. v. t. 19, f. 5. 
Spirogyra mirabilis, Kutz Sp.p. 438. Petit Spirogyra p. 14, 
t. 8, f. 3-4. 
Conjugata longata, Gray Arr. i. 279(?) 
var. B. turpis. 
Sterile cells abbreviated. 
Zygnema malformatum, Hass. Alg. t. 30,f. 1,2. Ann, Nat. 
Hist. x. (1842) p. 39. Jenner Fl. Tunb. Wells, 180. 
Zygnema cateneforme, Hass. Alg. t. 30, f. 3, 4. Ann. Nat. 
Hist. x. (1842), p. 39. 
Zygnema abbreviatum, Hass. Alg. t. 34, f. 4. 
