180 
OF THE FUNGI. 
clean through cork and leaf, sections of the required thin- 
ness may be obtained without difficulty. To keep the 
two pieces of cork from shifting during the operation, they 
may be thrust through a metal ring of suitable size, or a 
piece of stout paper may be gummed round them ; a still 
simpler plan is to tie them together with strong thread or 
thin string. The section can be placed at once on a slide 
with a fine hair pencil. 
In a large number of cases the fruit must be examined 
in a dry state, in order to ascertain the true connection of 
the spores with their receptacles, as water causes them to 
separate. Of this description is the whole order of Botry- 
tacese or Hyphomycetes — an order which embraces most of 
the common 1 moulds,’ growing upon organic substances, 
both dead and living ; the Peronospora of the potato, to 
which I lately alluded ; the parasites which infest the 
onion, pea, rose, and clover, and numerous other pests of 
the farm and garden. In all these (which to the naked 
eye appear as patches of a white woolly substance) the 
fruit, or acrospores, as they are called in technical lan- 
guage, are situated on the tips of certain upright threads, 
sometimes solitary, but more generally branched, so as to 
have the appearance of miniature forest trees, only that 
there are no leaves, and that each branchlet supports at its 
apex a single round or oval acrospore. In some cases the 
branchlet itself is moniliform, or made up of rows of these 
tiny reproductive organs, adhering end to end. 
From some unknown cause, the 4 pedicels’ no sooner 
come in contact with water, than they 1 lose their heads ; ’ 
the fruit drops off, and the observer misses the chance of 
ascertaining the way in which pedicel and acrospore were 
united. If then a fluid is applied at all, a single drop 
must be laid on the slide after the specimen has been placed 
ready for examination. Let the water touch the covering 
glass, and it will creep under by capillary attraction and 
saturate the object. 
