60 Thirty-second Report on the State Museum. 



or less tinged with dark-red, or brown tinged with yellow or greenish-yellow. 

 In a few species the final color is less decided, approaching a dark-umber or 

 snuff-brown. Sometimes the outer stratum, lying next to and in contact with 

 the inner surface of the peridium, is paler than the rest of the mass. With 

 this change in the color of the interior mass there is also a change no less 

 wonderful in its character. It is now no longer moist and fleshy, but dry and 

 dusty. The whole interior is filled with a soft but elastic mass of intricate, 

 slender, cottony filaments interspersed with countless multitudes of minute 

 dust-like spores. This mass of threads is called the capillitium. In some 

 species it is of nearly uniform density throughout, but in others those filaments 

 that spring from the base do not so freely unite and intermingle with . those 

 that spring from the walls of the peridium. They, therefore, form a central 

 mass more or less distinct from the rest, and are called the columella. The 

 columella is usually of a somewhat conical shape, but sometimes it is nearly 

 globose. It may be detected in the mature plant by carefully making two 

 opposite slits in the peridium, extending them from the apex nearly or quite 

 to the base, and then opening the two hemispheres thus formed, the uncut 

 base acting as a hinge on which the halves may turn. The columella, if 

 present, will be seen projecting from the base in the center of the cleft. The 

 slits are best made with a pair of small, sharp scissors, as care should be taken 

 not to disturb the natural position of the filaments more than is necessary. 

 In the mass the capillitium and spores appear to be uniformly and similarly 

 colored, but often if the filaments are cleared of the spores tlieyare seen to be 

 paler in color. Rarely they are darker. The color of the capillitium and 

 spores might be used as a character for grouping our species in subsections. 

 The spores in all our species are nearly or quite globose. They vary in size 

 in the different species from .00016 to .00025 of an inch in diameter. The 

 olive-tinted spores in nearly all the species are smooth and about .00016 of 

 an inch in diameter, but the purple-tinted ones are always rough or echinulate 

 and generally larger, varying from .0002 to .00025 of an inch broad. It is 

 perhaps needless to say that the size of the spores does not at all depend on 

 the size of the plant that produces them. The spores of the Griant puff- 

 ball, the largest one of the genus, are but .00016 of an inch in diameter, while 

 those of the little Smooth puff-ball, which is scarcely more than an inch in 

 diameter, are about .00025 of an inch broad. The color of the. spores may be 

 ascertained by ejecting a small quantity of them on white paper or by opening 

 the peridium and exposing them to view. 



Puff-balls rarely make their appearance in the early part of the season. 

 Old effete specimens of the preceding autumn may be found in early spring, 

 flattened and closely pressed to the ground by the snows of winter. Fresh 

 specimens rarely appear before the middle of June. Their greatest abund- 

 ance is in late summer and early autumn. During the months of August, 

 September and October most of our species occur. One species I have 

 found in July and August only, another in July only. (Some species are 

 invariably found in cleared lands, others in woods or bushy places, while a 

 few are denizens of both field and forest. Some grow on the ground only, 

 others on old logs and decaying wood, and a few on both the ground and 

 decaying wood. One southern species is said to inhabit the bark of living oak 

 trees. Some species have distinct, whitish, root-like fibres at the base. These 

 penetrate the earth, and sometimes creep through it for a considerable dis- 

 tance. In the Pear-shaped puff-ball they are generally well developed, and 

 sometimes several individuals are found to be attached together by these 

 creeping subterranean fibres. 



In the determination of the species, it is desirable to have specimens in 

 both the mature and the immature condition. The former will afford the 



