The Saprophytic Fungi of Eastern Iowa. 

 The Puff-balls. 



By T. H. MACBRIDE and XORRA ALLTX. 



The puff-balls constitute an exceedingly interesting section 

 of our fungous flora. They include the largest forms known 

 to the class and are so common as to be in most of their forms 

 very generally observed and named by the common people. 

 To the botanist they possess especial interest as being the 

 highest of their class, i. e. as evincing the limit of differentia- 

 tion in the possibilities of fungal life: in diversity of form, spe- 

 cial adaptations for the dispersal of their spores and general 

 complexity of structure throughout, the puff-balls as a group 

 transcend all other fungi. 



The most striking characteristic of the puff-balls is the fact 

 that their spores are internally developed and remain in the 

 interior of the fructification until ready for dispersal. (See 

 vol. i. p 33 and p. 181). The basidia. hyphal branches upon 

 which the spores finally appear, project into chambers of 

 greater or smaller dimension and regularity and these cham- 

 bers suggest for the group containing the puff-balls its scien- 

 tific name, Gasteromycetes (Greek, gasteron^ a sac. etc.). The 

 form and character of the spore-chamber, its development 

 and final dehiscence vary greatly within the limits of the 

 group as will in the course of our further discussion of the 

 subject well appear, but the variations all have reference to 

 the one function of spore-dispersal; the general formation of 

 the spores is the same in all. 



As to their life-historv, some of the puff-balls seem to be 

 annuals, that is. from the spore develop to complete fructi- 



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