872 NOTICES OF BOOKS. 
touching their morphology and ee teen amt ali that 
to Pri 
is due ringsheim, there is much to learn; thus as relates to the 
Semaidatial of the oospores, this has nies observed in only thre 
species, one each b ons eim, Cleve, a w ilst their 
0 
efforts in this Sirestion had not produced much r 
e Gdogoniea\form a Family sufficiently eslidaieed; on the one 
hand the Coleoebadtsn approach them, on the other the Spha aropleee. 
These three Families would see m to form to together a single Class, 
f 
should be —? Cdogoniacee. This Class might be defined asfollows:— 
Edogoni : Cellular plants (of the fresh water), forming confervoid 
filaments with chlorophyllaceous cells, simple or bsdataae rarely 
ing parench omatic 
produced by fecundation, in germination giving rise to zoospores ; 
agamosp res motile (zoospores), formed mer in each vegetative cell 
(such zoospores not yet observed in Sphero, 
The family @dogoniee consists of two ‘ti stinet genera, Zdogo- 
nium, Link, and Bulbochete, Ag., as already set forth by Prings- 
species of dogonium form two sub-sections—one contains those species 
which possess dwarf males epiphytic on the female plants (‘‘ nannan- 
drous ” species) —the other such as have male plants of the same mag- 
degree in different species. Those which most approach the monoicous 
forms have male plants so little developed that they contain but one cell 
(‘ unicellular nannandres’’), all spermogonium, the contents of which 
become divided into two motile ease pire Other species there are 
in which the dwarf male plants consist of a t least two cells, one in- 
ferior which remains ssiccmer Gi gin 3 Ar one or a few superior 
ar uni 
cellular. A few nannandr ecies with outer pete 
imes th 
were, forming a connecting link between the nannandrous OF ot 
mre bg _— The dwarf sate have their origin from a sical 
kind o: oospores Ciihiensoces: Pringsheim); these are produced 
most in sartaie cells androsporangia) of the female individuals ( By- 
porous species,” Pringsheim), or they are produced i in certain 
cells of neuter individuals (“ idioandrosporous species. 2) 
* Pringsheim : ‘‘ Beitrige zur Morphologie und Systematik der Algen: me 
phologie der Eiogonien, ” in his Jalebaotee fiir Wiss, Botanik,” ’B.i., pt 
te 
