It is very tough, and opens by an irregular rupture or lacerated 
aperture. It grows on the ground, either in fields or thin woods, 
often persists through the winter in its brown mature con- 
ition. 
We have two or three species of Scleroderma or hard-rind 
puff-balls, in which the flesh, even in young plants, is not white, 
but rather of bluish-black or purplish-black. ‘These have not 
been recorded as edible, and though they are not known to be 
poisonous, they do not come under the rule given for edible 
pufi-balls, and should be omitted entirely; yet one correspondent 
reports having eaten them and liking them. 
IV. MORELS AND HELVELLAS. 
These belong to a large class called Discomyceteae, “disk 
fungi.” The spores are produced in thin membranous sacks 
(usually eight in each), imbedded in the flesh of the upper or ex- 
terior surface of the cap. This character is not easily seen with- 
out a microscope. Comparatively few of the species are large 
enough and tender enough for food. 
Morels are neither like puff-balls nor like mushrooms. They 
consist of a stem and a cap or head. The cap, which is the spore- 
bearing part, is either globose, oblong, conical or cylindrical in 
shape, according to the species. But its most marked feature, 
and the one by which morels are the most readily distinguished 
from all other fungi, is found in the small depressions or cavities 
which occupy its whole exterior surface, giving it a somewhat 
honey-combed or pitted appearance. The intervening ridges or 
dissepiments are rather thick and blunt on the edge. In all our 
species the caps are yellowish, buff or ochraceous when fresh and 
growing, but they usually assume darker or brownish hues as 
they mature and begin to dry or decay. The stems are rather 
stout, hollow, and white or whitish, sometimes tinged with yel- 
low. They are not polished, but slightly roughened by numer- 
ous minute branny particles. In some species the stems are often 
shorter than the head or cap. 
The species may be grouped in two sections. In one, the low- 
er margin of the head grows fast to the top of the stem; in the 
other, it is free from the stem, as in the cap of the common mush- 
room. in the former case the head is hollow, in the latter there 
is a cavity beneath it, or rather an open space, between its mar- 
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