Bovista. Dill.
The genus Bovista differs from Lycoperdon in several ways. When the Bovista ripens it breaks from its moorings and is blown about by the wind. It opens by an apical mouth, as does the genus Lycoperdon, but the species of Bovista have no sterile base. They are puffballs of small size. The outer coat is thin and fragile and at maturity peels off, leaving an inner coat firm, papery, and elastic, just such a coat as is suitable for the dispersion of its spores. Leaving its moorings at maturity, it is blown about the fields and woods, and with every tumble it makes it scatters some of its spores. It may take years to accomplish this perfectly. The species of the Lycoperdon do not leave their moorings naturally; their spores are dispersed through an apical mouth by a collapse of the walls of the peridium, after the fashion of a bellows, by which spores are driven out to the pleasure of the wind. In Bovista the threads are free or separate from the peridium, but in Lycoperdon they arise from the peridium and also from the columella.
Bovista pila. B. & C.
The Ball-Like Bovista.
Photo by C. G. Lloyd.
Plate LXIII. Figure 471.—Bovista pila.
Natural size of matured specimens.
Pila means a round ball. The peridium is globe-like, sessile, with a stout mycelium, a cortex thin, white at first, then brown, forming a smooth continuous coat, breaking up at maturity and rapidly disappearing.
The inner peridium is tough, parchment-like, elastic, smooth, persistent, purplish-brown, fading to gray. The dispersion of spores takes place through an apical mouth. The capillitium is firm, compact, persistent, at first clay-colored, then purple-brown; threads small-branched, the ends being rigid, straight, pointed. There is something so noticeable about this little tumbler that you will know it when you see it, and if you often ramble over the fields you will soon meet it. However, I have as yet seen only the matured specimens.