4 2 



NATURAL HISTORY BULLETIN. 



no one specimen is very large, the largest perhaps ten inches 

 in diameter. Isolated individuals, on the other hand, reach 

 remarkable dimensions. Our largest specimen was 16 inches 

 in diameter; specimens three feet in diameter are reported. 



By the ancients the giant puff-ball was denominated boz'is/a, 

 doubtless because of supposed medicinal value in veterinary 

 practice. " Pulvere maturo hujus et afinium cum lacte mixto 

 Borussi Fennones in diarrhoea bourn utuntur." Juries, Syst. 

 Myc. in, 30. Limueus wrote Ly coper don bovista; Schaeffer, 

 A. maximum; Morgan Calvatia maxima, etc. 



2. Calvatia pachydermum [Peck) Morgan. 



Sporocarp subglobose, 4-6 inches in diameter the rooted 

 base somewhat pointed; outer peridium thin, smooth, whitish. 

 the upper part cracking into small, irregular, persistent, spot- 

 like scales or areas; inner peridium thick, sub-corky, some- 

 what brittle above, at length breaking up into irregular frag- 

 ments; capillitium and spores ochraceous-brown; threads 

 long, flexuous, somewhat branched; spores subglobose or 

 broadly elliptical, 4-6 « x 5~7 /■'• 



Growing on the ground. 



Our best specimen is very large being about 16 inches in 

 diameter or 4 feet in circumference. The thin, white, outer 

 peridium breaks first and shrinks back in patches somewhat 

 smaller than the fragments of the inner peridium which fol- 

 lows, in breaking, the same lines. We have one specimen 

 from Guthrie County about 12 inches in diameter and one 

 from Muscatine about 16 inches in diameter, both much larger 

 than the description would seem to warrant, but the species is 

 so well marked that there can be no doubt of correct reference. 



Rare. The range seems westward. Reported so far here- 

 tofore from Dakota and Arizona. 



3. Calvatia cyathiformis (Bosc) Morgan. 



Sporocarp 2-4 inches wide, broadly obovoid or turbinate, 

 depressed or flattened above, with a short, thick base and cord- 

 like root; outer peridium smooth, thin fragile, easily peeling off, 



