195 



fascicles of branches lateral, more or less dense, spreading arti- 

 culations more or less swollen, nearly equal in length and 

 diameter, constricted at the joints, cell contents granulose, 

 effused. 



SIZE. Cells 'Ol-'Olo mm., of branches 'OOS-'Oll mm. 



Kutz. Tab. Phy. iii., t. 21, f. 2. Rabh. Alg. Eur. iii., 385. 

 Kirch. Alg. Schl. p. 70. Eng. Fl. v., 389. ' Eng. Bot. ii., t. 

 2546. Harv. Man. p. 122. Jolmst. Fl. Berw. ii., 261. Mack. 

 Hib. p. 222. Hook. Fl. Scot, ii., p. 76. Hass. Alg. 125, t. 9, 

 f. 1, 2. 



Batrachospermum fasciculatum, Vanch. Conf. p. 116, t. 13. 



Ulva incrassata, Eng. Bot. i., t. 967. Hucls. Fl. Ang. ii., 

 572. With. AIT. iv., 124. 



Conferva geiatinosa Dames cornu, Ray Syn. p. 60. 



Tremella geiatinosa Dama cornnum,T)i\l. Muse. 51, 1. 10, f. 10. 



Rivularia incrassata, Purton Mid. Fl. iii., p. 179. 



Myriodactylon endivce/olium. Gray AIT. i., 302. 



In ditches, &c. 



Exceedingly variable in the form of the thallus, and hence divided 

 into 7 or 8 varieties. 







Plate LXXFIII. -jig. 2. , plants ra endivcefi lia, 



natural size, b, portion of filament X < liani. 



Chaetophora punctiformis. Kutz. 



Ecliinella articulata, Eng. Bot. ii., t, i 



Conferva echinata, Eng. Bot. i., t. 1378. 



Assuming that Mr. W. Phillips (Grevillea 

 correct in the presence of globose basal spores, this 

 to find a place in Rivularia, and not in Chcetophora. 



GENUS 74. COLEOCH-ffiTE. .5;^. (1844.) 



Articulated filaments branched, either united in a pulvimile, 

 or little cushion, or expanded in a flat, somewhat disc-shaped 

 parenchymatous thallus ; cells oblong, more or less dilated in 

 front, sometimes bearing from the back or upper surface a 

 hyaline bristle, which is sheathed at its base. 



Propagation by oospores resulting from sexual fertilization, 

 and by zoogonidia. Zoogonidia single in the fructiferous cells, 

 either globose or broadly oval, furnished with two vibratile cilia. 



The ColeochaBteae are small discoid Algae, from 1 to 2 mm. in diam., 

 bright green colour, constructed of branched rows of cells. They are 

 found attached to submerged plants in stagnant or slow-moving streams, 

 and form circular, closely-pressed discs. The chlorophyll is in parietal 

 plates or large grannies. Some of the cells bear colourless erect bristles 

 fixed at the base in narrow sheaths. 



2 E 



