CHAPTER XIV. 



PUFF-BALLS: LYCOPERDACEAE. 



This is not the place for a discussion of the different genera of 

 the puff-balls, etc., but it might be well to say that in recent years 

 the old genus Lycoperdon has been divided into several genera. The 

 giant buff-ball, and the L. cyathiforme, where the wall or peridium 

 ruptures irregularly, have been placed in a genus called Calvatia ; 

 certain other species which are nearly globose, and in which the wall 

 is of a papery texture at maturity, are placed in the. genus Bovista. 

 There is one genus belonging to the same family as the lycoperdons, 

 the species of which are very interesting on account of the peculiar 

 way in which the wall is ruptured. This is the genus Geaster, that 

 is, "earth star." The wall, or peridium, is quite thick in the 

 members of this genus, and when it matures it separates into several 

 layers which need not all be discussed here. A thick outer portion 

 which separates from a thinner inner portion further splits radially 

 into several star-like divisions, which spread outward and give to the 

 plant the form of a star. Since the plants lie on the earth the name 

 earth star was applied to them. This opens out in dry weather, 

 even curving around under the plant, so that the plant is raised above 

 the ground. Then in wet weather it closes up again. The inner 

 portion of the wall opens at the apex in various ways, in the different 

 species, so that the spores may escape. A closely related genus has 

 several small perforations like a pepper box in the upper surface of 

 the inner wall, Myriostoma. 



LYCOPERDON Tourn. 



To this genus belong most of the ** puff-balls," as they are com- 

 monly called, or, as they are denominated in the South, ** Devil's snuff 

 box." All, or a large portion, of the interior of the plant at matur- 

 ity breaks down into a powdery substance, which with the numer- 

 ous spores is very light, and when the plant is squeezed or pressed, 

 clouds of this dust burst out at the opening through the wall. The 

 wall of the plant is termed the peridium. In this genus the wall is 

 quite thin, and at maturity opens differently in different species. In 

 several species it opens irregularly, the entire wall becoming very 

 brittle and cracking up into bits, as in the giant puff-ball. In the 



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