Dar bishire.- — On Actinococcus and Phyllophora. 267 
EXPLANATION OF FIGURES IN PLATE XV. 
Illustrating Dr. Darbishire’s paper on Actinococcus and Phyllophora. 
Actinococcus subcutaneus (Lyngb.) K. Rosenv. 
Fig. 1. Longitudinal section through the apical portion of a spermophore of 
Phyllophora Brodiaei. The dark cells stained with iodine represent the cells 
of the parasite, which has entered the host through the ostiole of the antheridial 
cavity (at a). The parasite is branching in between the cells of the host. A 
differentiation is already visible in the former into a root and shoot portion, 
x 2 50 diam. 
Fig. 2. General view of a longitudinal section through the apex of a spermo- 
phore of Phyllophora Brodiaei , which has been successfully attacked by the 
parasite, Actinococcus subcutaneus. The intramatrical filaments, stained dark blue 
with iodine, are clearly seen. From these arise the extramatrical filaments, which 
have passed out of the tissue of the host, through the cortex. They have formed 
a nemathecium, only part of which is seen in the drawing. To the left of the 
section, at #, are seen four small antheridia-lined cavities, x 170 diam. 
Fig. 3. A single shoot-filament of the parasite breaking through the cortex of 
the host. The outer covering of the latter is apparently undergoing some change, 
x 400 diam. 
Fig. 4. A bunch of shoot- filaments of the parasite forcing their way through 
the cortex of the host. They are much branched, x 400 diam. 
Fig. 5. A branching filament of the parasite forcing its way between the 
medullary cells of the host-plant. The arrow points in the direction of the cortex, 
x 400 diam. 
Fig. 6. Section through the basal attachment of an older nemathecium, showing 
clearly the boundary between the host and the parasite, x 400 diam. 
