195 
2. ZYGNEMACEAE. 
Mougeotia, De Bary, 1858. 
*M. glyptosperma, De cnp Conj., 18, t. 8, fig. 20-25. Tancality 
and date uncertain (Wright !). 
Sirogonium, Kiitz., 1843. 
S. sticticum, Kütz. Phyc. gen., 278. Common at the north end 
of the lake in the early part of the year, 1902. Zygospores not 
observed. 
Spirogyra, Link., 1820. 
S. crassa, — loc. cit., 280, t. 14. fig. iv. Laboratory tank, 
all the year round; ioter bingiad with Zygnema pectinatum in 
water-lily dodi, June, 1902; moat, July, 1902. Zygospores not 
observed. This is the only species of Spirogyra to be found in 
the gardens during the winter months ; the others only appear in 
March and April. A well-developed iieath is frequently to be 
found surrounding the filaments. 
S. nitida (Dillw.), Link, Handbk., iii., 262. Laboratory tank 
(Massee !); amongs her Pascenueads inn in a tank in the 
Herb. Dptmt., with zygospores, June, 190 
S. a (Vauch.), Cleve. Monogr. Zygn., 22, t. 5, fig. 8 to 13. 
Middle tank of water-lily house, June, 1902. "A very variable 
d . 
Var. * = Cooke. Lake, June, 1902. Zygospores not 
observe 
Var. b. decimina, Cooke. Temperate house pools, inter- 
mingled with other Algae, June, 1902. Zygospores not 
observed. 
Var. c. rivularis, Cooke. Victoria regia tank ; with zygo- 
spores, pem. 902. 
S. condensata ( Vauch.), Ktz. Tab. Phyc. v., t. 22, fig. iii. Laboratory 
tank, July, 1902 ; moat, July, 1902. Zygospores not observed. 
S. longata (Vauch.), Ktz. Phyc. germ., 222. Laboratory tank, 
June, 1902, with aygosror es. The varieties communis and turpis, 
oe were both pre 
S. insignis (Hass.), Ktz. Spec. Alg., 438, n. 12. Moat, May, 
1902 ; with zygospores. 
S. Weberi, Ktz. Phyc. Gen., 279, n. 4, t. 14, fig. 3. On the stone- 
bird of the fountain in the pond, J une, 1902. Zygospores not 
observed. 
Form. a. inaequalis, Cooke. Laboratory tank, August, 1902. 
Form. b. subventricosum, Cooke. Gro n lea 
Biri s»iralis in middle tank of deiude hu "05, 
June, 1902. With zygospores. 
13757 
N2 
