of the Genus Doassansia, Cor mi. 41 
The sori are situated for the most part in the uppermost 
layer of the palisade-parenchyma just under the stomata. A 
cross-section through the centre of a spot shows 15 to 20 of 
them closely packed together. They are nearly globular, 
often somewhat flattened vertically, and measure 60 /x to 100 
M by 75 /x to I4 o They appear of a very dark brown at 
the periphery, and of a much lighter colour in the interior. 
The spores are very firmly compacted together, yet with 
numerous though very small spaces between them. They 
are irregularly polygonal in shape, 6 /x to 12 ju, in diameter, 
with moderately thick, light-brown outer walls, and pale 
contents with a single large or a few small oil-globules. The 
sori are invested with a compact layer of hyphae. Over 
some portions this layer is several hyphae thick, in other 
places a single layer only is present. The hyphae have 
thickened walls and are very dark brown (Figs. 65 a and 65 b). 
This cortex is more pronounced than in either of the two 
preceding species, and in some sections (cf. Fig. 65 b with Fig. 
66) appears to be almost as true a cortex as is present in D. 
epilobii. But the hyphal character generally shows (as in 
Fig. 65 a), and this is not the case in D. epilobii. 
Owing to the lack of fresh material, or even of material 
comparatively recently collected, the germination of the 
spores could not be obtained. Cross-sections through the 
older spots showed that nearly all of the spores of the older, 
more central sori had germinated in position. The upper 
part of the sorus, as well as the epidermis of the leaf, had been 
ruptured, and each sorus had a bunch of long filaments, the 
promycelia and sporidia, projecting from it and extending 
beyond the surface of the leaf. The promycelia could be 
seen distinctly and resembled those of D. alismatis. The 
sporidia were very long and slender (70 /x by 1 y), and 
appeared to germinate by tubes, but both the arrangement 
of the sporidia on the promycelium and the details of their 
germination were not satisfactorily determined. 
Season. Mr. Rau’s specimens were collected in the early 
