GASTEROMYCETES 



473 



gradually swell, increase their membranes and become brown. These 

 are the future capillitium threads; their form and sculpture are important 

 systematic characters in separating Bovista from related genera, as 

 Globaria and Mycenastrum. At maturity, the peridium opens at the 

 top, the gleba disintegrates into a dry powder which is penetrated by a 

 tangle of capillitium. 



In the cosmopolitan Lycoperdon, which has given this family its name, 

 formation of the fructification takes place as in Bovista, only the gleba 

 G is differentiated into a fertile and sterile zone (Fig. 300, B). Thus, 

 as in Bovista, the whole interior of 

 the fructification is constructed of 

 a thick tissue knot covered with a 

 hyphal palisade. In the lower 

 columnar part of the fructifica- 

 tion, the later stipe st, glebal de- 

 velopment is retarded; the glebal 

 chambers retain their original 

 rounded form and the hyphal 



Fig. 300. — Lycoperdon gemmatum. A. Exterior of fructification (X \i). B. Section 

 of young fructification ( X 2). Pa, outer peridium; Pi, inner peridium; Zw, middle layer; 

 C, rudimentary columella; G, gleba cavities, sterile below, fertile above; St, stipe. (After 

 Rehstciner, 1892, and Strasburger's textbook.) 



palisade remains sterile. In the upper capitate part (Fig. 300/), how- 

 ever, the cavities become compressed by rapid growth of the tramal 

 plates, into long and narrow labyrinthine, radiating and often tortuous 

 slits in which the hymenia deposit their spore masses. In the species 

 with more or less cylindrical fructifications, as in L. gemmatum, the sterile 

 part gradually passes over into the fertile; in the species with capitate 

 fructifications, as L. depressum, there is a sharp line between the rapidly 

 developing fertile and the retarded sterile part. This line has been 

 formed by a horizontal pulling apart of the fertile and sterile chambers 

 the transition zone (Rabinowitsch, 1894). The exoperidium 



in 



is 



