CHAPTER VI 
CLASSIFICATION AND PHYLOGENY 
The Uredinales form a group of Fungi so closely allied that 
they must be regarded as monophyletic. The number of species 
considered in the present work is about 250. They may be 
divided into five families. 
A. IJMPEDICELLATA. 
I. Melampsoracese—Teleutospores not pedicellate, but 
seated on a dilated hyphal cell, produced singly in the 
tissues of the host, or compacted side by side into flat crusts, 
1—4-celled. Germination by an external basidium, with 
minute round basidiospores (about 10). Uredospores ab- 
stricted singly. Aicidia with or without a peridium. 
II. Cronartiaceee—Teleutospores not pedicellate, produced 
in chains, which are either separate or united into columnar, 
wart-like, or lens-shaped bodies. Germination asin I. Basidio- 
spores round, small (about 10 yu or less), 
III. Coleosporiacee—Teleutospores in one (or rarely two) 
layers, forming waxy, bright-coloured crusts, not pedicellate, 
but seated on a dilated hyphal cell, at first one-celled. Ger- 
mination by the formation of an internal basidium of four 
superimposed cells, each of which protrudes a sterigma and a 
large basidiospore (about 20 «). 
IV. Endophyllaceze—AKcidio-teleutospores surrounded by 
a hemispherical peridium and produced from a fusion-cell, in 
chains with intercalary cells, but germinating with an external 
basidium. 
