SCLEROD ERMA TALES 143 



^ Order 12. SCLERODERMATALES. 



The thick-skinned puff-balls of which the common Scleroderma 

 vulgare is the type, belong to the Sclerodermataceae. The species 

 are not numerous, but some of them are quite widely distributed 

 and abundant. Our common species grows about old stumps and 

 buried roots and is easily recognized by its rough warty exterior 

 and solid structure which, before maturity, is a bluish lead color 

 within; later it ruptures irregularly to scatter its spores. 



Scle7'oderi)ia flavidimi is very abundant southward, often grow- 

 ing in clusters along walks and in partly cultivated ground. S. 

 Geaster opens by irregular star-like teeth. The species of Poly- 

 saccum contain sporangioles so closely packed together that they 

 often become angular ; one species in the south frequently be- 

 comes as large as the double fists. The American species have 

 never been comparatively studied. The genera reported with us 

 are as follows : '^ 



1. Enclosing sporangioles at maturity. 2. 

 No sporangioles at maturity. 3. 



2. Wall of peridium single. Polysaccum. 

 Wall of peridium double, thin. Arachnion. 



3. Peridium distincdy stalked. PHELLORlNA.f 

 Peridium sessile or with a root-like base. Scleroderma. 



The last genus is the only one which is in any way common. 

 Two or three species occur in the Northern States and as many 

 more in the South. 



LITERATURE. 



Saccardo. Sylloge Fungorum, 7 : 133-154, 489-491 ; 9 : 278- 

 280 ; II : 167, 168. 



This group as well as that of the three preceding orders was 

 elaborated by Dr. J. B. De Toni for Saccardo' s Sylloge. 



* The genus Cenococctim hitherto referred here has very uncertain rela- 

 tions and may not belong to this order or even class. Massee (Jour. 

 Mycol. 5 : 184. 1889) has originated a genus Stella with a double pe- 

 ridium, the outer star-like, founded on a South Carolina species, but noth- 

 ing is known of such a plant on this side of the Adantic. 



I This genus is not well known. A single species from California was 

 described by Peck (Reg. Rep. 43: 35). 



