104 ZYGOPHYCE.E. 



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. , sterile cells X 400 ; b, fertile cells, with 

 zygospores, X 400. ]?iq. 5, var. ovalis. a, sterile cells X 400 j b, fertile 

 cells, with zygospores, X 400. 



tt Spore membrane smooth. 

 Mesocaxpus 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, 3. Jenner Fl. Tunb. 

 Wells 184. 



Sphcerocarpus par-rulus, 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. 



Sphcerocarpus angustus, Hass. Ann. Nat. Hist. xii. 187, t. 7, 

 f. 16. 



Mixed with other Algre, in ponds, &c. 



Plate XLII. fig. 3. a, sterile cells X 400 ; b, c, fertile cells, with zygo- 

 spores, X 400. Fig. 4, var. an g list us. a, sterile cells X 400 ; b, 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, f. 7. Rabli. Alg. Eur. iii. 257. Kutz. Tab. 

 Phy. v. t. 5. 



Mesocarpus intricatus, Hass. Alg. 1 67, t. 43, f. 1. Jenner 

 Fl. Tunb. Wells 184. 



tiphcerocarpus intricatus, Hass. Ann. Nat. Hist, xii, 186, t. 

 7, f. 9. 



In boggy pools, &c. 



