Cystocarp in R ho do me l aceae (II). 193 
is, moreover, represented as stretching across between the 
carpogonium and the superior cell cut off from the pericentral 
cell. This, I have no doubt, represents the conjugation of 
the carpogonium and an auxiliary cell, which, though it was 
inferred that it occurred in Rhodomelaceae, had not previously 
been observed in any species in the family. The fertilization 
of an auxiliary cell by the carpogonium has been directly 
observed in Dudresnaya , Poly ides, Gloeosiphonia , and other 
genera representing different families of the class Crypto- 
neminae. Schmitz also in his later researches (11) observed 
this fusion in the Ceramiaceae among the families of the class 
Rhodomeninae. I have myself during the last summer seen 
the conjugation-process in Antithamnion plumula , Thur. ; but 
I had hitherto failed to observe it in the Rhodomelaceae. 
The figure is a faithful drawing, by means of a camera lucida, 
of the appearance presented. A thick short process is seen 
extending between the carpogonium and the auxiliary cell. 
In the section it was deeply stained by the Hoffmann’s blue, 
and in this respect, as well as in the general appearance, 
corresponded closely with the conjugation-process which 
I had previously seen in Antithamnion plumula. The prepara- 
tion, however, left much to be desired. While the continuity 
of the process with the auxiliary cell was clear, it was directed 
obliquely against the carpogonium so as to prevent the con- 
tinuity with that cell being equally clearly traced. I regret 
that, in spite of many attempts, I have not been able to repeat 
this observation in other sections. Once, indeed, in the same 
situation I found a process, which I have no doubt was the 
remains of the copulation-tube. In the Ceramiaceae, Schmitz 
found that a small corner of the carpogonium was cut off, which 
fused with the auxiliary cell by means of a short tube. Whether 
anything corresponding to this occurs in Dasya could not be 
determined in the preparation. The observation leaves no 
doubt, however, that in Dasya , at any rate, the cell which 
plays the role of the auxiliary cell, is the one which I had 
previously called the sporogenous cell. The pericentral cell 
is not here the auxiliary cell. And I have little doubt now 
