132 ON THE THREAD BLIGHT OF TEA. 
where there is considerable moisture accompanied by heat. 
In such situations Dictyonema sericeum is not infrequent, 
and is generally felted with a green alga; and D. spongiosum, 
a far finer species with the same cracked hymenium, occurs 
in Cuba. Polyporus fruticum grows in the same island on 
living shrubs, often clasping the twigs, while Rhizina spong- 
iosa grows vertically in similar situations gorged with water ; 
besides which we have Cora pavonia, Thelephora pedicellata, 
Hypolyssus Montagnei, in similar situations, and, what is per- 
haps more nearly to the purpose, Rhizomorpha corynephora. 
There were one or two parasites on the leaves belonging to 
the epiphyllous lichens of the genus Strigula, but scarcely in 
a sufficiently perfect state to give their specific names. One 
of these (fig. 2 a) had perfect minute black perithecia con- 
taining clavate asci with linear curved sporidia ‘0001 inch 
long (fig. 3). Besides these were little shield-like bodies 
Fic. 3, asciand sporidia from (A), magnified. 
consisting of cells radiating frem a central aperture con- 
taining oblong, staff-shaped, triseptate spores, hollowed out 
at the sides, ‘001 inch long, on slender pedicels, and inclosing 
a pale green endochrome (fig. 4). Whether these are a 
Fig. 4, discs with spores, magnified. 
state of some Strigula or of some minute ascomycetous fungus 
