MOXOGRAPn OF THE LABOULBEXIACE.'R. 
211 
structure, consisting of higlilj specialized cells, or groups of cells, within ^vlli(•h tlie 
ids are foi-incd eiulogenously and fi 
y arc di 
special orifice in tlie form of free, naked, or nearly naked protoplasmic masses. 
Among such antherldia two distinct classes may be clearly distinguished, which I have 
termed simple and compound, respectively : although instances occui- in which aniheridia 
of the " simple " type are so closely associated that they mny be regarded as tran- 
sitional forms between the two types. In the first class, the simple form is character- 
ized by the fact that the antheridial cell is quite Independent of any similar cells, 
however closely they may be united to it, and discharges its antherozoids into the 
dium through its proper 
I 
hand, several such cells, closely associated to form a specialized organ, discharge their 
antherozoids into a common cavity from which the latter make their escape into the 
surrounding medium through a single aperture. 
The simple antlicndium (Plate II, fig. 15) is usually a more or less Hask-shnped cell, 
which may be solitary or associated with similar cells grouped together with or with- 
out regularity. Although in Amorphomyces, a genus wholly destitute of appendages, 
it results from the direct modlQcation of the terminal portion of the germinating 
spore (Plate V, figs. 20 
genera as a terminal or lateral 
from the appendage or its branches. In a majority of genera, if it does 
not terminate the appendage or one of its branches or branchlets, the antherldium is 
itself a branchlet, as, for example, when it is sessile ; but in a few instances this termi- 
nal character is lost and the organ is formed as a definitely intercalary cell, as in 
Rhadinomyces. lu the compound type, these cells seem always to be intercalary 
in ori^rin, althou"-h material has not been available for the study of their development. 
The form of tlie simide anthcridiuin is remarkably constant, the single cell of which 
iiturity, becomes 
it is composed being distinguished, more or le?s abruptly, into a baf 
flated portion or venter; and a terminal, more slender, usually sub-cy 
the neck, originally developed as a terminal outgrowth, which, at n 
perforate at its apex for the discharge of the male elements. The cavity of the ven- 
ter is separated from that of the neck by a kind of diaphragm, abruptly distinguished 
on the venter side, and much less so on the neck side. This diapl 
to be formed by the deposition of a ring of cellulose in the position indicated, is per- 
forate in the middle so as to allow the contents of the venter to pass out into the neck 
throucrh an opening which is mucli suialler than the diameter of the cavity of tlie 
neck itself (Plate I, fig. 26). The cavity of the neck therefore, which may be 
tly called the canal, though of about the same diameter throughout the 
