US TIL A G1NALES 8 1 



6. Spores borne in a more or less deliquescent gleba which is at first en- 



closed in an egg-like sac (peridium), but at maturity elevated on an 



elastically expanding receptacle ; (stink horns). 8. Phallales. 



Spores remaining within the peridium until maturity 7- 



7. Basidia united into a hymenium which lines the walls of irregular 



cavities. 8. 



Basidia uniformly distributed through the peridium, or forming skein- 

 like masses. 12. Sclerodermatales. 



8. Hymenial cavities remaining together within the peridium, their bound- 



aries mostly disappearing at maturity. 9. 



Hymenial cavities (sporangioles) separating at maturity from the cup- 

 like peridium ; (bird's nest fungi). n. Nidulariales. 



9. Remaining fleshy until the maturity of the spores ; no capillitium. 



9. Hymenogastrales. 



Fleshy when young, at maturity filled with dust-like spore masses mixed 

 with capillitium ; (puff-balls). 10. Lycoperdales. 



The above grouping is necessarily artificial and should be con- 

 trasted with the following more natural arrangement : 



1. Hemibasidii : Ustilaginales. 



2. Protobasidii : Uredinales, Auriculariales, Tremellales. 



3. Autobasidii : All the remaining orders. 



The relations of some of the lowest types are not yet clearly 

 known, and the relations of the entire group to other plants are 

 even more obscure. 



Order i. USTILAGINALES. 



The smuts form a group of parasitic fungi too well known to the 

 farmer since they result in the loss of a large percent of his crops 

 annually, notably among the cereals. The common corn smut is a 

 familiar example. It commences to make its appearance as small 

 distorted nodules either in the young kernels, in the tassels, or 

 quite frequently at the joints of the stems. These nodules in- 

 crease in size, becoming spongy, white, and glistening ; spore for- 

 mation is progressing, meanwhile, and the entire tissue soon be- 

 comes rilled with a black mass of greasy spores which form the 

 reproductive bodies of the fungus. Other species are parasitic in 

 the heads of wheat, barley and oats ; others still are found in the 

 leaves of various grasses forming long lines of black spores and ex- 

 ternally resembling black rust, but readily distinguished by the form 

 6 



