136 SIPHOPHYCER. 
Microspora floccosa. (Ag.) Thuret. Rech.t. 17, f. 4-7. 
Articulations before division about twice as long as the 
diameter, after division about equal, or a little shorter, slightly 
constricted at the joints. 
Sizz. Threads -015--017 mm. diam. (according to Kirschner 
*0075--01 mm. diam.). 
Rabh. Alg. Eur. iii., 321. Thuret. Ann. Sci. Nat. 1850, t. 
17, f. 4-5. 
Conferva floccosa, Ag. Syst. p. 89. Kutz. Tab. iii., t. 43. f. 
3. Eng. Fl. v., 351. Eng. Bot. ii., t. 2474. Harv. Man. 126. 
Mack. Hib. 224. Gray Arr.i. 310. Kirsch. Alg. Schl. p. 79. 
Lyngbya floccosa, Hass. Alg. 223, t. 60, f. 1-2. Jenner, Tunb. 
Wells, 188. 
Conferva fugacissima, Dill. Conf. Supp. t. B. 
In stagnant water. 
Plate LIII. fig. 3. a, b, portions of threads X 300; ¢, cells divided 
across for the escape of zoogonidia X 300; d, zoogonidia. 
Genus 59. CONFERVA. (Linn.) Link. (1820.) 
Articulate threads simple, articulations cylindrical. Chloro- 
phyllose mass homogeneous or granulate, including starch 
granules. 
Vegetation by division in one direction. 
Propagation unknown, (? by resting-spores which subse- 
quently produce zoogonidia). 
Recently Wille las declared his belief in the universality of resting- 
spores in the whole genus Conferva,* although it is hardly clear what 
is his conception of the limits of the genus. In a new species which he 
has described under the name of Conferva Wittrockii, he gives detailed 
account of spore formation, which it is presumed may be accepted asa 
type of what usually takes place. 
“The chlorophyllaceous contents contract, and become rounded. The 
colouring matter collects principally in the ends of the cells, so that the 
substance in the middle appears almost colourless; but after the con- 
traction of the cell contents the chlorophyllaceous portions of the 
protoplasm draw nearer together, until at last they coalesce and form a 
round or elliptical body within the mother cell; they then begin to 
surround themselves with a membrane, which later consists of two 
distinct layers. The spores are generally set free by the filaments 
resolving themselves into H shaped cells (in which the cell wall of each 
cell has a transverse fissure in the middle of the transverse walls); the 
spores then fall out. Sometimes they escape by the cell walls becoming 
converted into mucilage, their layers becoming gradually indistinguish- 
able. On first germinating, the size of the spores increases, as the 
result of which the outer membrane bursts. The outer membrane 
consists of two pieces with pointed ends, one being much larger than the 
* Ofversigt af Kon. Vetensk Akad Forhandl. xxxviii (1881). ‘Journal of Royal 
Microscopical Society,” Dec., 1882, p. 836. 
