33 
the formation of two partitions at right angles to one another. These 
partly separate, holding together only at one end, which becomes one 
pole of the globular cluster subsequently formed by ig erie aici ; 
the other pole only closing in when a large number of cells have been 
formed. e cells are then carried apart from one another by the 
hyaline investment formed by each; and the characteristic Volvox 
sphere is thus completed.” 
Order IV. CONJUGATZ (Link), De Bary. 
Pamiry VII. ZYGNEMACEZ (Menegh.), Rabenh. 
. 
Multicellular algw. Cells cylindrical, equal at both 
In filamentous families, forming an articulated simple thread, with a 
central cytioblast involved in radiating protoplasm. Cell-walls 
lamellose. 
_ Chlorophyll-mass effused, or of a definite form, often forming a 
spiral band. Vegetation by repeated transverse divisions. pa- 
Pras by zygospores, resulting from the conjugation of two cells. 
“Snjugation taking place in three ways—lateral, scalariform, and 
genuflexuous.—Cooke’s British Freshwater Algw, 74 
This family is subdivided into three sub-families according to 
the character of the reproductive process:—I. Zygnemew.; Il. Meso- 
carpe ; and III. Gonatonemee. 
cthey omusation in the present family is the union of two cells, 
se formation of a zygospore. The cells containing the male an 
ay element cannot at present be distinguished from each other, 
bout De Bary states that he has observed a constant difference 
ae i. the fertile and sterile cells of a species of Spirogyra. Usually 
l the 
ar Benak the male and female filaments would seem to be distinct, 
nt this requires more certain confirmation, i uch as in such 0 
= qered, and a little pullulation or process is pushed out, are 
ie ly coats itself with cellulose and rapidly enlarges to a considerable 
Tr, , : 
ster, at the same time growing in length until it meets a similar 
tleno esting out from an oppontile cell or has attained as great 
Meet th a8 its laws of development will allow. When’ two pore 
ey become fused together, the end walls are ruptured, ar th 
= ane of one cell assing over are received within those 0. she 
ot else the contents of both cells meet within the connects g 
goed t ere use together. 1is is the more comm . d 
connecting tube. It is evident that, if the ce 
their fullest extent, there will be 3 Bee te and a 
ng tubes as there are pairs of cells in the filaments, 
oth ends; 
fructiferous cells more or less tumid or in ated, all closely conjoined ° 
4 
