264 Darbishire. — On Actinococcus and Phyllophora . 
upwards of 250 cells. As yet it still remains to be seen what 
actually becomes of these products of germination. Possibly 
they would normally have attacked a new host, be this Phyll. 
Brodiaei or some perfectly different plant, on which ultimately 
the carpospores would possibly be formed. The carpospores 
perhaps, one might almost say probably, germinate on 
Phyll . Brodiaei , and eventually give rise to the nemathecia of 
Actinococcus subcutaneus . It is not to be wondered at that 
the parasite should be able to live separately for nearly two 
years in an artificial culture, when it is borne in mind that its 
cells contain rhodoplastids. The long filaments are probably 
searching for a suitable substratum, whereas the larger 
aggregations of cells represent portions of the thallus which 
are chiefly assimilating. On the other hand, the form of the 
plants resulting from the experimental germination of the 
tetraspores of Actinococcus may be due to the very abnormal 
conditions under which germination took place. 
In discussing the question a short time ago with Professor 
Reinke, the latter suggested as a possibility, which ought not 
to be dismissed prima facie, that Actinococcus might really be 
an asexual generation of Phyll. Brodiaei , growing parasitically 
on the sexual generation. Although this is not absolutely 
impossible, it is not very probable that it represents the true 
state of affairs. I need only recall to mind the fact that the 
contents of one antheridial cavity at least are destroyed by 
the parasite entering the host. 
The foregoing paper was written for the purpose of de- 
finitely settling the nature of the pseudo-nemathecia of 
Phyll. Brodiaei (Turn.) J. Ag., of the parasiticum quid of 
Lyngbye, of Actinococcus subcutaneus (Lyngb.) K. Rosenv. 
and Act. roseus Ktz., all of which represent the nemathecia 
of Actinococcus subcutaneus (Lyngb.) K. Rosenv. 
Other species of Phyllophora Grev. and of other closely 
related Gigartinaceae and other species of Actinococcus Ktz. 
and allied genera, are about to be examined by the author. 
It is a remarkable fact that the nemathecia of Phyll. Brodiaei 
have not yet been found, although this species is as common 
