CARPOPIYTA. 163 
Practical Studies.—(q) Search for cup-shaped fungi, in the spring, 
about old hot-beds and upon well-rotted barnyard-refuse. The com- 
mon Cup-fungus of an amber color (Peziza vulgaris) often to be met 
with in such localities is one of the best for tlie study of spores and 
spore-sacs. Make very thin sections at right angles to the inner sur- 
face. ‘This species may be readily preserved in alcohol for future 
study. 
(®) Collect the bright-red saucer-shaped plants growing in the 
woods upon decaying sticks and having a diameter of 1 to 4.cm. 
Make similar sections. 
(c) Collect a few Morels (Morchella esculenta), and make sections at 
right angles to the surface of the pits which cover its upper portion, 
for spores and spore-sacs. The Morel, which grows in the woods, is 
an amber- or straw-colored fungus 10 to 15 cm. high and having an 
egg-shaped pitted top, 3 to 6 cm. in diameter, borne upon a thick 
stalk, both stalk and top being usually hollow. The whole growth 
above ground (which is edible) is to be regarded as a spore-fruit. 
339. The Black Fungi (Order Pyrenomycetes).—The 
plants of this order are parasitic or saprophytic in habit; 
their tissues are usually hard and somewhat coriaceous, dif- 
fering in this respect from the Cup-fungi, which are generally 
fleshy. In many respects the Black Fungi are much like 
the Cup-fungi, to which they are doubtless closely related. 
340. A good illustration of the plants of this order is 
the Black Knot (Plowrightia morbosa) which attacks the 
plum and cherry. In the spring the parasitic filaments, 
which the previous year penetrated the young bark, mul- 
tiply greatly, and finally break through the bark and form 
a dense tissue. The knot-like mass grows rapidly, and when 
full-sized is usually from two or three to ten or fifteen cen- 
timetres long (.8 or 1.2 to 4. or 6. in.), and from one to three 
centimetres in thickness (.4 to 1.2 in.); it is solid and but 
slightly yielding, and is composed of filaments intermin- 
gled with an abnormal development of the bark-tissues of 
the host-plant. 
341. The knot at this time is dark-colored, and has a 
