Medical Officers of the Army of India
41
and these bundles are often seen to limit abruptly the extension of mycelial
invasion. When the petiole is attacked it is also greatly hypertrophied, the
areas of transverse sections through normal and attacked petioles being in
the ratio of about 100 to 170. Such transverse sections, through attacked
petioles, show that the aecidia are laid in the fundamental parenchyma tissue,
below the hypoderma. The fundamental parenchyma cells are throughout
considerably hypertrophied, for, whilst in transverse sections the normal cells
measure in outline from 57 x 38µ to 82 x 50µ, those among mycelium measure
from 95 x 63µ to 139 X 88µ.
The teleutospores by transmitted light are pale yellow, double-celled
bodies, Puccinia, with long stalks, which, as already stated, are surrounded
by a gelatinous sheath, swelling considerably in water (Fig. 13, Plate I). The
free end of the upper cell is usually perceptibly thickened. The spores vary
greatly in size from a total length of 74.0 to 50.8µ. The upper cell was found
to vary in size from 38µ in length by 16µ in breadth to 25 X 15µ and the
l ower cel l f r om 36 X 16µ t o 25 x 15µ. The spor e i s sl i ght l y const r i ct ed at
the septum, which measures usually 14µ in breadth. These spores are detach
-able with difficulty, not only from their beds, but from one another, as they
tend to break off in masses when scraped off by a needle. The stalks are
from 2 to 2½ times as long as the whole length of the spore, i.e. about 125 to 156µ
and when swelled in water they are about 12µ in diameter. A nuclear space is
sometimes clearly defined in each cell, but not always. The epispore is smooth
and without any markings. When the stalk is swelled in water the central thin
axis is clearly defined, as in Gymnosporangium. The spores germinate in water
very readily, throwing out a promycelium from each cell, into which the pale
yellow contents of the spore body wander, accumulating in the distal extremi
- ties (Fig. 14, Plate II), leaving the proximal parts filled with colourless fluid. The
promycelium of the upper cell emerges from the apex of the cell, and that of
the lower from a point near the septum, as in most Puccinia, but unlike
Gymnosporangium. From this point the further developmental phenomena are
curious, and until the issue of the last Botanische Zeiting, 1 which I have just
received, unlike those of any hitherto described species. The observations made
in this number of the Botanische Zeitung by F. Kienitz-Gerloff on the peculiar
development, at times, of the teleutospores of Gymnosporangium clavariœforme
add considerable interest to the Smilax fungus, for, whilst before there was only a
morphological resemblance, which might well have been of little or no importance,
we have now a biological resemblance, and both together suggest a closer re
-lationship between Gymnosporangium and the other Æcidiomycetes than has
hitherto been suspected. The ends of the promycelia certainly usually divide into
four cells (Fig. 15 c, Plate II) by transverse septa much in the usual way, but
those cells, instead of producing sporidia, at the ends of sterigmata, round off at
1 B o t a n i s c h e Z e i t u n g , N o . 2 5 , 2 2 n d J u n e 1 8 8 8 , p . 3 8 9 .
G