104 ZYGOPHYCES, 
There seems to be no specific difference between the two species of 
S. depressus and S. ovalis of Hassall, the only feature relied upon being 
that the filaments in the latter are scarcely more than half the diameter 
of the former. 
Plate XLI. fig. 4. a, sterile cells X 400; 4, fertile cells, with 
zygospores, X 400. Hig. 5, var. ovalis. a, sterile cells X 400; 4, fertile 
cells, with zygospores, X 400. 
tt Spore membrane smooth. 
Mesocarpus parvulus. (Hass.) De Bary. 
Sterile cells 5-12 times as long as broad. Zygospore spheri- 
cal; membrane even, commonly twice the diameter of the 
threads. 
Size. Cells ‘01 mm. Zygospore :02--024 mm. 
De Bary Conj. p. 80, t. 2, f. 15. Cleve Mon. Zyg. p. 31, t. 
9,f.6,7. Hass. Alg. 169, t. 45, f. 2, 8. Jenner Fl. Tunb, 
Wells 184. 
Spherocarpus parculus, Hass, Ann. Nat. Hist. xi. 434, t. 7, 
f. 13, 14. 
Mougeotia splendens, Kutz. Tab. Phy. v. p. 1. 
var B. angustus. Hass. 
Mesocarpus parvulus, var. tenuissima, De Bary Conj. t. 11, f. 
10-14, 
Mesocarpus angustus, Hass. Alg. 170, t. 45, f. 4. 
Spherocarpus angustus, Hass, Ann. Nat. Hist. xii. 187, t. 7, 
f. 16. 
Mixed with other Algz, in ponds, &c. 
Plate XLII. fig. 3. a, sterile cells X 400; B, ¢, fertile cells, with zygo- 
spores, X 400. Fig. 4, var. angustus. u, sterile cells X 400; 3, fertile 
cells, with zygospores, X 400; c, mature zygospore X 400. 
Mesocarpus scalaris. (Hass.) De Bary. 
Sterile cells 2-4 times as long as broad; zygospore spheri- 
cal or broadly ovoid; membrane brown, even, about equal in 
diameter to the threads. 
Size. Cells 034 mm. diam. Zygospore ‘034 mm. diam. 
De Bary Conj. p. 80. Cleve Mon. Zyg. p. 32, t. 9, f. 
11,12. Hass. Alg. 166, t. 42, f.1. Hass. Ann. Nat. Hist. x. 
p. 45; xii.t. 7, #7. Rabh. Alg. Hur. iii. 257, Kutz. Tab. 
Phy. v. t. 5. 
Mesocarpus intricatus, Hass. Alg. 167, t. 43, f. 1. Jenner 
Fl. Tunb. Wells 184. 
Spherocarpus intricatus, Hass. Ann. Nat, Hist. xii, 186, t. 
7, f. 9. 
In boggy pools, &c. 
