Report of the Botanist. 59 



suddenly compressed, it emits a little cloud of spores which bears some resem- 

 blance to a puff of smoke. This probably suggested the name "Puff-balls." 



There are two other closely related genera in this order, whose species 

 emit the characteristic puff of spores. One is called Bovista, the other 

 Scleroderma. In the former, the outer rind or epidermis disappears as the 

 plant matures, and there is no distinct spongy or cellular mass of sterile 

 tissue at the base of the plant. In the latter, the walls of the plant are 

 thick and firm when young, and they remain in nearly the same condition 

 when mature. In these respects both genera differ from the genus Lycoper- 

 don. In it the fertile part of the plant is more or less globose in shape, but 

 there is always a mass of coarse empty cells at the base, which constitute a 

 sterile part of the plant — that is, they produce no spores. In those species 

 which have this part highly developed, it constitutes a sort of stem to the 

 fertile part, and raises it above the earth or the matrix on which the plant 

 grows. When the sterile base is but slightly developed, the plant appears to 

 sit directly on the ground or matrix, and is then said to be sessile. The 

 exterior of the plant consists of two parts. The outer part is sometimes called 

 the bark, sometimes the exterior peridium. In some species it takes the form 

 of minute flocculent or pulverulent masses of scurf-like scales, in others it 

 consists of weak spines or spine-like bristles, while in others still the spines 

 are much longer and stouter, being thickened at the base. Plants with these 

 coarse long spines are said to be echinate, because of their stiff bristly aspect. 

 Sometimes several contiguous spines have their tips curved toward each other 

 and united together, thus forming little stellate or star-like clusters. These 

 external processes or adornments are often called warts. In some species 

 they are deciduous at maturity, in others they form a permanent adornment 

 of the inner rind or true peridium, but in such cases they usually shrivel 

 with age and become less conspicuous. In a few species, the exterior peri- 

 dium, at maturity, is separable from the inner, and may be peeled off like a 

 thin membrane. The inner or true peridium is at first rather thick and firm, 

 but when fully mature it is generally thin, membranaceous and flaccid. In 

 one series of species, the upper part, when mature, breaks up into irregular 

 fragments and soon falls away ; in another series it bursts by a small apical 

 aperture, and then remains in this condition a long time. This difference in 

 the periclia of the various species affords a character by which the genus is 

 divided into two sections. The first section was designated by Fries as 

 Bovistoides, the other as Proteoides. The former was raised by Rostkovius 

 to the rank of a genus with the name Langermannia, but modern mycologists 

 have generally followed Fries in regarding these species as a section or sub- 

 genus of Lycoperdon. 



The peridium incloses at first a soft fleshy mass of white cellular matter. 

 If a minute portion of this be examined microscopically, a great number of 

 short jointed filaments and enlarged cells or basidia are seen, the latter of 

 which bear slender spicules, usually four apiece, on the tips of which the spores 

 are borne. When the plant is fully developed, this central fleshy substance 

 becomes filled with moisture and quickly changes its color. So abundant is 

 the moisture that it may be pressed out like water from a wet cloth or sponge. 

 The inexperienced collector is sometimes surprised at finding the moisture in 

 the specimens which he has laid up to dry increasing instead of diminishing, 

 and his surprise is soon changed to disappointment and perhaps annoyance, 

 when he sees his beautiful specimens \vater-soaked and discolored by this 

 superabundance of moisture. In most species the white color of the flesh at 

 first changes to a yellow or greenish-yellow, but this hue soon becomes darker 

 until at last it is either a purple-brown or a dingy-olive ; that is, brown more 



