324 THE STUDY OF MINUTE FUNGI. 
dead branches lying about, and especially an overhauling of one 
of the little piles of drift wood about the roots of some tree on 
the bank of a creek, will furnish you material for a year’s work, if 
properly used. On one or more of the branches you have picked 
up you will find a portion thickly dotted with black spots, which, 
under a hand magnifier will be seen to be little black bodies, 
closely united and bursting through the bark. These are really 
the ends of as many tubes, which are the necks of globular, oval 
or retort-shaped flasks buried in the bark or wood beneath. By 
slicing off with a sharp knife, thin horizontal sections of the bark, 
through one or two of these little pustules, you will be able to se 
Fig. 75. 
pear black and 
empty with 
thick walls. 
With the 
point of a knife 
pick out one or 
two of these 
flasks, put them 
ae on a glass slide 
a, Valsa on a fragmentof branch, natural size. b, perpendicular sec- with a drop of 
tion. c, Asci and p hyses. d, spores, e, ho - 
ceptaculum and perithecia. shg T ESE O 
water, and a 
rather thick cover, and crush them out flat by pressure. Examin- 
ation of the object thus prepared, with a power of about two hun- 
dred and fifty diameters, will show that the contents of the flasks 
are little colorless delicate sacs, in each of which are eight minute 
colorless, curved, sausage shaped spores. 
The little sacs are called thecæ, or more usually asci, the flask i 
which encloses them being called the perithecium. And the Spheer- 
iacei are Fungi in which the. Spores are contained in asci (as- 
comycetes) and the asci are produced in perithecia, which are 
more or less globose, at first entirely closed, at length opening by 
a neck (ostiole), or pierced by a small hole or pore at the summit. 
If each perithecium is by itself, or solitary, not imbedded in a 
crust or stroma, but either on, or in the bark or wood, it is called 
a simple or true Spheeria. 
