28 Charles E. Bessey 



of one or two kinds ; asci and basidia here replaced by one-, two-, 

 or several-celled teliospores. (About 4,200 species.) 



Order Uredinales. Rusts. Typically producing five kinds of 

 spores, viz., (i) thin-walled sporidia, (2) smooth- walled pycnio- 

 spores, (3) aeciospores, (4) uredospores, (5) teliospores, of 

 which 3 and 4 are forms of conidia. 



Family 133. Aecidiaceae. Teliospores free or fascicled, usu- 

 ally erumpent; sporidia, pycniospores, aeciospores, uredospores, 

 and teliospores typically present; walls of spores usually firm. 

 Uropyxis, Phragmidium, Aecidium, Nigredo, Uromyces, Dicae- 

 oma ["Puccinia"). (Pf. I, i**, 48.) 



Family 134. Uredinaceae. Teliospores compacted into a crust 

 or column, subcuticular or erumpent, walls of spores firm. Uredo 

 {" Melampsora"), Cronartium. (Pf. I, i**, 38.) 



Family 135. Coleosporiaceae. Teliospores compacted laterally 

 into waxy layers ; walls of spores weakly gelatinous. Coleospo- 

 rium. (Pf. I, I**, 42.) 



Order Ustilaginales. Smuts. Typically producing two kinds 

 of spores, viz., (i) thin-walled sporidia, (2) teliospores, which 

 are here regarded as homologous with the teliospores of the pre- 

 ceding ordeir. 



Family 136. Ustilaginaceae. Germinating teliospore produc- 

 ing a septated promycelium. UstUago, Sphacelotheca. (Pf. I, 

 I**, 6.) 



Family 137. Tilletiaceae. Germinating teliospore producing a 

 tubular promycelium. Tillctia, Entyloma. (Pf. I, i**, 15.) 



FUNGI IMPERFECTI. The Imperfect Fungi. Here are 

 collected from 16,000 to 17,000 species of fungi with regard to 

 which our knowledge is quite imperfect. We do not know their 

 ascigerous states, if indeed they have any, but it is generally 

 assumed that they are the conidial states of Ascosporeae, and 

 that possibly in some cases they have lost all else through excess- 

 ive degeneration. They are mostly parasitic. For the present 

 they must be grouped here, and treated as though they were 



64 



