142 ['sfilagiiiaccct — Tillctiacece. 



III. Spores in balls — 



A. Sori powdery. 



a. Spore-balls rather temporary, 



6. Sorosforium. — Germination by simple promyceliuni witliout 



conidia or by septate promyceliuni with lateral and terminal 

 conidia. 

 h. Spore-balls permanent. 



7. Thecaphora. — Germination by elongated septate promyceliuni 



only producing a single terminal conidium. 



8. Tohjposporium. — Germination by septate promyceliuni with 



lateral and terminal conidia. 



B. Sori agglutinated. 



a. Spore-balls composed of spores with thick epispore. 



9. Tolyposporella. — Germination by branched septate promycelium 



producing single lateral conidia. 

 h. Spore-balls with peripheral spores and central sterile cells. 



10. Testicularia. — Spore-layer surrounded by a membrane of 



firmly united large round cells. Germination unknown. 



TILLETIACEiE Tul. 



Sori forming powdery erumpent spore masses or permanently imbedded 

 in the tissues. 



Germination by means of a short promyceliuni, usually producing a 

 terminal cluster of elongated conidia, which, with or without fusing in pairs, 

 produce similar or dissimilar secondary conidia, or directly give rise to infection 

 threads. 



I. Spores, single — 



A. Sori powdery at maturity. 



a. Spores without conspicuous hyaline appendage. 



11. TUletia. — Germination by short promyceliuni with terminal 



cluster of elongated conidia, which, with or without fusing 

 in pairs, produce a germ-tube. 

 h. Spores with elongated hyaline appendage. 



12. Neovossia. — Germination as in Tilletia, and the conidia 



produce a germ-tube without fusing. 

 B. Sori permanently imbedded in the tissues. 



a. Spores scattered in patches through the tissues. 



13. Entyloma. — Germination similar to Tilletia, and often in 



addition tufts of conidia formed on protruding hyphae. 



b. Spores in extended layers throughout the whole or portion 



of the plant. 



14. Melanotaenium. — Germination by short stout promyceliuni, 



with terminal conidia not separating, but fusing in pairs. 



II. Spores in balls — 

 A. Sori powdery. 



a. Spore-balls with sterile peripheral cells. 



15. C/roc^/s^w.— Germination as in Tilletia, or the terminal 



cluster of conidia produce directly long infection threads. 



