718 
Transactions of the Society. 
Genus Zygnema Ag. 
Many sterile species, from various localities, were seen, but none 
were observed in conjugation. 
Genus Debarya Wittr. 
D. glyptosperma (De Bary) Wittr. R. 
Order Desmidiace^i. 
Genus Gonatozygon De Bary. 
G. Balfsii De Bary. L., B., R., 0., Brandretb. 
G. Brebissonii De Bary. L., B., R., S., Brandreth, 
G. minutum West. Bn., Stye Head Tarn. 
*G. Kjellmani Wille. 
Forma minor et recta. 
Long. 58 p ; lat, 6-6 * 5 p, Bo. 
Genus Sphserozosma Corda. 
S , vertebratum (Breb,) Ralfs. B., R., Bassenthwaite Water. 
forma minor West (Addit. to the Fresbw. Alg. of W. 
Yorks, in Naturalist, 1891, p, 244), Fig. 3. Hp,, Sk, 
B, R. 
S. excavatum Ralfs. Frequent. 
S. granulatum Roy et Biss. Bn., W. 
Genus Spondylosium Breb. 
S. pulchellum Arch. Hp., Grisedale Tarn. 
S. pyqmseum (Cooke) West (Contrib. Fr. Wat. Alg. of W. 
Ireland, p. 116). 
var. compkessum var. n. Fig. 4. 
Yar. cellulis subquadrangularibus, compressis ad polos. 
Long. cell. 5 * 5-6 p ; lat. cell. 7 p ; lat. isthm. 2 *5 p. B. 
Genus Onychonema Wallick. 
0. filiforme (Ekrnb.) Roy et Biss. Bn. 
Genus Hyalotheca Ehrnb. 
H. dissiliens (Sm.) Breb. Very frequent. 
At 2400 ft. on Helvellyn. It was seen with zygospores from 
Harrop Tarn, Bowness, Loughrigg and Hawkshead. 
forma bidentula (Nordst.) Boldt. , B., Bn., L., Sk. 
var. Mans Wolle. Bt., Sk., C., Hk., Lake Side. 
War. tatrica Racib, (Nonn. Desm. Polon., p. 8, t. xiv. 
f. 5). 
Long. cell. 20 p ; lat. 16-16*5 p. Hk. 
H. mucosa (Dilhv. ?) Ehrnb. B., R, S. 
