258 THE NORTHERN MICROSCOPIST. 
MICRO-FUNGI IN NOVEMBER. 
S November approaches, micro-fungi accumulate in a marvellous 
manner : the innumerable leaves lately green and beautiful on 
the trees have been scattered in all directions by the autumnal 
winds, and lie about in a state of decay, but upon them, almost 
without exception, there still is life. The leaf-fungi of the spring 
and summer have for the most part consumed that portion of the 
leaves on which they were developed, and as they become matured 
have been carried away to lay the foundations of other crops in 
the coming year. A rounded hole is all that remains to testify to 
the destruction which the fungus has effected. Let us now gather 
a few leaves from the ground and examine them. Sycamore and 
maple leaves are very abundant, especially if our search be ina 
wood, which now is the best hunting ground for the student. If 
this be his first hunt of the kind, he will be startled at the strange 
black patches he finds upon the above-named leaves, some assum- 
ing singular arrangement of configuration, others being mere large 
patches of intense black; not unfrequently the black spots are 
arranged on the leaf somewhat artistically, but in all cases they 
have a shining, undulating surface, and are easily recognised. I 
shall never forget my first find of the well-known fungus, AAytisma 
acerinum, in a wood at Chelford, early in my microscopic study. 
Since then, I have frequently met with it. Willow leaves furnish 
us with another Rhytisma, 2. sadicinum, and the nettle another, 7. 
urtice, but these, although easily seen, are not so conspicuous as 
R. acerinum. ‘There is one other to which I must refer, namely, 
Rhytisma maximum, which makes its home upon branches of the 
willow, and when in good condition is a most interesting object. 
Then the spores in asci may be easily obtained and prepared for 
microscopic inspection. I have always been more or less disap- 
pointed in the examination of other Rhytisma, but never with this. 
It may be known by its shining surface, but the dimpled character- 
istic of other Rhytisma is absent. 
The genus Dothidea should now be looked for. Various of them 
have made their appearance earlier, but many linger on to the end 
of the year. The one on the rush, D. junct, is an annual visitor, 
and may now be met with on the margins of pools where rushes love 
to grow. ‘Another, which is very common, is D. filicina, braken 
Dothidea. Almost every stem of /teris aguilina is more or less 
infested with this fungus. Some of the Dothidea grow on decayed 
herbaceous stems, as D. s¢rieformis. Gooseberry branches are 
sometimes infested with Dothidea ribesta, Other plants become 
the homes of other Dothidea, but it is not desirable that I should 
occupy more time with this genus. 
