202 



MICROSCOPIC FUNGI. 



C-ZSOMACEI. 



Spores of gne order — 



Simple and free. 

 Without appendages, 



Springing from delicate threads • 



Produced in separate cells. — 



Deeply seated, pulverulent, 

 generally nearly black . . 



Superficial, yellow or brown 



l\ot inclosed in separate cells 



With appendages. 



Deciduous 



Permanent 



Compound. 



Irregular 



Subglobose or shell-shaped 



Spores of two orders — 



1. Spherical 



2. Cylindrical, septate 



1. Spherical 



2. Wedge-shaped, compact 



1. Concatenate, exposed . . . • I 



2. Spherical, concealed . . . . ji 



TiLLETIA, Tul. 



Spores spherical, reticulated, proceeding from delicate branched 

 threads. 



Tilletia caries, Tul. Bunt; included within the germen; 

 sjjores spherical, rather large, black.— On wheat, filling the grains 

 with dark-coloured spores, fetid when crushed. Autumn. Very 

 common. (Plate V. figs. 84 — 91.) 



UsTiLAGO, Link. 



Plant deeply seated. Spores simple, springing from delicate 

 threads, or in closely-packed cells, ultimately breaking up 

 into a powdery mass. — Berk. Outl., p. 335. 



Ustilago segetum, Ditm. Corn Smut ; produced on the 

 receptacle and rachis ; epidermis soon ruptui'ed ; spores loose, 

 minute, globose, black. — On the ears of corn and grasses. Autumn. 

 Very common. (Plate V. figs. 98, 99.) 



Tilletia > 



Ustilago. 



Uredo. 

 Lecythea. 



Trichobasis. 

 Uromyces. 



Polycystis. 

 Tuburcinia. 



Coleosporium. 



Melampsora, 



Cystopus. 



