MICHIGAN ACADEMY OF SCIENCE. 
(b) Catastoma subterraneum (Pk.) Morg. 
Other name: Bo vista subterranea Pk. 
“Spores globose, distinctly warted, 6-8 mic., sessile”; otherwise similar to 
the preceding. Reported in 4th. Report by Longyear. In sandy fields. 
3. Bovista. 
(a) Bovista pila B and C. 
Other names: 
Bovista stuppea Berk. 
Bovista tabacina Sacc. 
Mycenastrum Oregonense E. and E. 
“Spores globose, 3.5-5 mic., sessile or with minute pedicel.” Fruit-body 
over one inch in diameter. Cortex soon disappearing. Peridium dehiscing 
irregularly. Throughout the state, mostly in woodlots. Common around 
Ann Arbor. 
(b) Bovista plumbea Pers. 
Other names: 
Bovista nigrescens Pers. 
“Spores oval, even, 6-7 by 5-6 mic, with long hyaline pedicels.” Fruit- 
bocly less than one in. in diameter, dehiscent at apex; cortex shelling off in 
pieces; inner peridium lead colored. Our commonest Bovista. Through- 
out the state, in fields. 
4. Mycenastrum. 
Mycenastrum spinulosum Pk. 
A large puff-ball without a stem, up to 4 in. in diameter. Inner peridium 
almost woody and very thick. Spores in mass-purple brown, 9-12 mic. glo- 
bose, very minutely warted, often with minute pedicel. Reported by Long- 
year; on Campus, East Lansing. Other stations should be found. 
5. Calvatia. 
Key to species. 
(a) Fruit-body very large, 6 to 12 inches in diameter, without a dis- 
tinct stem-like base; almost filled by the spores.. . .Calvatia gigantea. 
(a) Fruit-body 3-5 in. or less in diameter, with a stem-like base. . . . (b) 
(b) Mass of spores violet or purple Calvatia cyathiforme. 
(b) Spore mass greenish-yellow or olivaceous (brown in age) 
Calvatia coelata. 
(b) Spore mass brown or brownish-olivaceous. Fruit-body abruptly 
•contracted into a stem-like base Calvatia elata. 
(a) Calvatia gigantea (Schaeff) Batsch. (In sense of Lloyd.) 
Other names: 
Calvatia maxima Schaeff. (In Morgan.) 
Bovista maxima. 
Bovista gigantea Nees. 
Lycoperdon bovista L. (In Trelease and Massee.) 
Lvcoperdon maximum Schaeff. 
Lycoperdon giganteum Batsch. (In Peck.) 
Globaria bovista (L) Quel. (In Engler and Prantl.) 
Globularia gigantea Guel. 
This is the common giant puffball growing in rich woods or grassy fields. 
It has been found at a number of stations around Ann Arbor. Distributed 
throughout the state. It is in great demand for the table, and is best pre- 
