CRYPTOGAMIA ALG^E. 257 



the joints is far from certain, for sometimes they fill nearly 

 the whole, and at others only a small portion of them." 



4. Z. gcnufiexum,) yellowish-green, soft, matted ; filaments slen- 

 der, brittle, here and there bent and combined by their angles ; 

 joints 4 times their diameter, partly filled with a green mass and 

 an interrupted single beaded line GREV. FL Edin- 320. Con- 

 fcrva genuflexa, DILLW. Syn. 51. t. 6. and t. c. Eng. Sot. t. 1914. 



Ilab. Moss pools on moors. Spring. 



The beaded granules are immersed in the green matter of 

 the articulations, each containing from 2 to 4 in a series. 

 They are omitted in the figures referred to, though dis- 

 tinct enough under the magnifier, and well represented by 

 VAUCHER in his admirable work on fresh water Conferva, 

 tab. 8. fig. 1-9. Many of the articulations are empty and 

 pellucid. The filaments are straight until they form their 

 junctions, when they become angled or kneed at irregular 

 intervals. 



The mode of reproduction in the Zygnemce is as curious as 

 their structure is interesting. In their progress towards 

 maturity the spiral lines become more and more widely 

 separate, and sometimes irregular ; and at length two fila- 

 ments unite themselves by means of short transverse 

 tubes at distant and uncertain intervals. The spiral lines 

 now lose their form, becoming in each joint one irregular 

 green mass, which in this state passes from its containing 

 joint into a corresponding one of the opposite filament 

 through the connecting tube, so that the articulation of 

 one filament is empty, and the other becomes filled with 

 the contents of two." They remain thus for some time, 

 when the filaments are destroyed or separate into small 

 portions, leaving the green matter free from its envelopes. 

 This matter is the seed, which, sinking to the bottom, re- 

 mains there until the ensuing spring recalls it into life. 



160. BATRACHOSPERMUM. 



1. B. moniliforme, olive-green, very lubricous, bushy ; branches 

 alternate, spreading, tapered, whorled at every joint with dense 

 tufts of dichotomous and moniliform filaments ; seeds in clusters 



in the axils of the whorled filaments VAUCH. Conf. 112. t. 11. 



f. 1. and t. 1. f. 5. Conferva gelatinosa, Eng. Bot. t. 689. DILLW. 

 Syn. 63. t. 32. 



