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Sierra Club Bulletin. 



is marked on the surface by broad pyramidal projections, 

 which are often an inch in diameter at the base and half 

 to three quarters of an inch high in the larger mature 

 specimens. The projections are regularly arranged and 

 give the dorsal side of the puffball the appearance of the 

 back of a tortoise. It is this peculiarity, connected with 

 the large size, which makes this pufifball so readily recog- 

 nized. No one can possibly make a mistake in regard to 

 its identity. All other large puffballs are either absolutely 

 smooth on the upper surface or else marked with minute 

 projections. The projections, then, on the surface of the 

 Sierran Pufifball are gigantic, especially when young. 

 Later they often split into three or four, remaining at- 

 tached by their tips, which also often become curved. 



At maturity, the whole pufifball becomes dry, the in- 

 terior being filled with a bright yellow, powdery mass 

 of spores and microscopic threads, while the thick outer 

 covering breaks up into pieces and falls ofif. In this 

 way the spores are exposed to the winds, which scatter 

 them, and thus spread the growths of puflfballs. Finallv 

 all the upper portion disappears, and nothing is left but 

 the stout stalk, more or less buried in the ground, and 

 some fragments of the upper portion and some traces of 

 the powdery spores. Two of these latter stages are repre- 

 sented, about one quarter the natural size, in the photo- 

 graph accompanying these notes. 



Like all other pufifballs, and in fact like all other 

 fleshy fungi, this one is seldom entirely free from insects, 

 which find shelter and food within its tissues, thus spoiling 

 the plants for good botanical specimens, and even hinder- 

 ing the proper maturing of the spores. Small specimens 

 are often found which from this or some similar cause 

 have been killed early in their development, and, while 

 not showing the efifects of the ravages externally, have 

 become mummified, or dried up. Such specimens show 

 the general characteristics well, but do not show the 

 important spore characters. Two such specimens are 

 represented in the lower right-hand corner of the photo- 



