PUFF BALLS 227 
more primitive structure, and that the basidium is a 
later and a higher structure, probably derived from it. 
376. There are about 14,000 species, which may be 
separated into nine orders, and about twenty-five fami- 
lies. A few only of these will be taken up here. 
377. The lowest of the Basidium-fungi, the False 
Tubers (Order HyYMENOGASTRALES) are subterranean 
plants, with subterranean truffle-like, fleshy fruits, which 
like the truffles are edible and wholesome. They are 
distinguished from the truffles by the fact that they con- 
tain basidia instead of asci. 
378. The Puff-balls (Order LycoprrpALzs). The 
plants of this order are saprophytes, whose spore fruits 
are often of large size, and usually more or less globular in 
form. The basidiospores are always borne in the in- 
terior of more or less regular cavities, and from these they 
escape by the deliquescence, and subsequent drying and 
rupture of the surrounding tissues. 
379. The vegetative filaments of Puff-balls penetrate 
the substance of decaying wood, and the soil filled with 
decaying organic matter. They 
usually aggregate themselves into Ca 
cylindrical root-like masses. After V2 
an extended vegetative period the 
filaments produce upon their root- ry. 108 —Puft-ball and 
like portions small rounded bodies, pomcicaperss. 
the young spore fruits, which increase rapidly in size and 
assume the forms characteristic of the different genera. 
380. No sexual organs have yet been discovered, but 
analogy points to their possible existence upon the vege- 
tative filaments just previous to the first appearance of 
the spore fruits. The spore fruits are composed of inter- 
laced filaments loosely arranged in the interior, and an 
external more compact limitary tissue forming a rind 
