HYALOTHE< \. 2 



_> 



occur elongated and strong. When gathered in proper season, 

 and kept in water for a few days, the cells separate at the artic- 

 ulations, and float in tree joints, which being nearly square, 

 readily turn over and present the circular end view, with the 

 stellate arrangement of the chlorophyl. I have had a quantity 

 in good condition for observing the successive stages of conju- 

 gation. The cells separated the same day the collection was 

 made: and Boon thereafter copulation of cells commenced. 

 Plate I, figs. 7, 8, are two Boating cell-, one in front and 

 the other in transverse view ; they are drawn to each other 

 by some hidden conjugal influence, put forth a mucous tube 

 ami unite a- fig. ''. then each cell breaks into two; thus four 

 part- are united: sometimes all present themselves to view, 

 hut more commonly only three arc visible, a- figs. 10 and 11. 

 The chlorophyl concentrate- to the -pace between the cell.-; 

 fig. 10, shows an early stag< ; fig. 11. a more advanced condi- 

 tion ; and Hl'. 12, the developed zygospore. Single matured 



zygosp are frequently noticed in gatherings from waters 



w hen- the plant prevai 



II. \ - \. M.ti Kali-. Plate I. fig. 13. 



Filaments scarcely fragile ; joint- not constricted, but having 

 at mil' of the end- a minute bidentate projection, the adjoining 

 end of the next joint being similar. These projections arc 

 visible onlv in older plant-. 



I tiameter 19-21 ". 



This plant i- not bo frequent aa the preceding, hut it 

 appear- to be widely distributed, not in masses, but frequently 

 mingled with other filamentous forms. Had it from ponds of 

 Pennsylvania, New Jersey, Vermont, Rhode Island, South 

 ( 'arolina and Florida. 



It i- easily distinguished from the preceding by its 

 wider mucous sheath, by the straight margin of the cells, by 

 the longer joint- and by the central gathering of the chloro- 

 phyl. The mucous -heath being entirely colorle i- not 

 easily discerned except when surrounded by turbid water. 



II. iNDt i ,,\ i.\. Nord. Plate LI I 1. fig. 8. 



< 'ell- about twice a- long a- wide, sides concave and angles 

 rounded, closely connected : filaments are involved in a wide 

 colorless gelatinous -heath. The constriction of the cells, and 

 the rounded angles make an undulate margin. 

 I Hameter !i-l 2 ". without -heath, 



