ZYGNEMACES. 108 
Gznus 49. MESOCARPUS. Hass. (1845.) 
Spore spherical or oval, between two cylindrical, straight or 
slightly in-bent lateral cells. (a) Copulation ladder-like, 
threads free, or with one end attached; (6) copulation lateral 
between two neighbouring cells of a thread, rarely ladder-like. 
Sterile cells often with a knee-like bend, and intergrown at the 
bend with similar cells of another thread. 
Including also the genera Pleurocarpus and Craterospermum of Braun. 
t Spore membrane scrobiculate or punctate. 
M. nummuloides, Hass. 
M. depressus, Hass. 
tt Spore membrane smooth. 
M. parvalus, Hass. 
M. recurvus, Hass. 
M. scalaris, Hass, 
Sub-gen, Pleurocarpus, Braun. 
M. pleurocarpus, De Bary. 
t Spore membrane scrobiculate or punctate. 
Mesocarpus nummiuloides. (Hass.) De Bary. 
Sterile cells 7-14 times as long as broad. Zygospore spheri- 
cal, or broadly ovoid ; membrane brown, scrobiculate. 
Size. Cells -015 mm. diam. Zygospore :044 X -084 mm. 
De Bary Conj p. 80, t. 8, f. 9, 10. Cleve Mon. Zyg. p. 
30, t. 9, f 4,5. Hass. Alg. 169, t. 45, f. 1. Rabh, Alg. 
Eur. iii. 257. 
Spherocarpus nummuloides, Hass. Ann. Nat. Hist. xii. 187, 
t. 7, f. 12. 
In ditches. Fruiting in September. 
Plate XLT. fig. 3. a, sterile cells X 400 ; }, fertile cells, with zygo- 
spores, X 400. 
Mesocarpus depressus. Hass. 
Sterile cells 7-12 times as long as broad. Zygospore ellipti- 
cal, compressed ; membrane brown, punctate. 
Size. ‘007-015 mm. 
Hass. Alg. 168, t. 44, f. 1. Jenner Fl. Tunb. Wells 184. 
Spherocarpus depressus, Hass, Ann. Nat. Hist. xii. 186, t. 
7,f. 11, 
var. B. ovalis. Rabh. Alg. Eur, 111. 257. 
Mesocarpus ovalis, Hass. Alg. 169, t. 44, f. 2. 
Spherocarpus ovalis, Hass. Ann. Nat. Hist. xii, 189, t. 7, f. 
15. 
In boggy waters. 
