740 



FUNGI 



stems of beans and vetches, the uredospore and teleutospore-sori 



being round or oval of chestnut-brown colour. 



(b) Uromyces BetcR Pers., is a common parasite on garden and 



sugar beet, mangel, and wild sea-beet. The ^cidiospores are 



rarely met with except on the 

 petioles and young leaves of 

 'seed '-beets in spring, but uredo- 

 spores and teleutospores are freely 

 produced in summer on the 

 ordinary mangel crop, their re- 

 spective sori being roundish and 



F,c. .50.-^, Uredospo^-sorlof mangel of brOWn ColoUr (Fig. 250) 

 rust (^Uromyces Bette Pers.) (enlarged 

 about 6 diameters) ; 5, teleutospore of 



A heteroecious species, namely 



mangel rust; C teleutospore of bean UrOMVCeS PtSt YeXS., is a frCQUent 

 rust {Uromyces FabcB Pers.). {B and C ^ ^^ ^ 



enlarged 320 diameters.) pest of the pea CrOp. ItS Secidio- 



spores are produced on the spurge, Euphorbia Cyparissias L. 



Ex. 309. — Examine the sori of Uromyces Beta and U. Faba with a pocket 

 lens ; make drawings. Scrape off with a penknife uredospores and teleuto- 

 spores of each ; mount in water and examine with high power. Observe that 

 both uredospore and teleutospore are unicellular ; note the differences in the 

 surface and thickness of the cell walls of the respective spores. 



Series B. — Autobasidiomycetes. 



II. The Autobasidiomycetes or second series of the Eubasidii 

 are characterised by their undivided unicellular basidia which 

 are club-shaped or cylindrical. Each basidium generally bears 

 at its apex four slender sterigmata on the end of which single 

 basidiospores are produced. 



More than 10,000 species of fungi are included in this series. 

 Most of them display considerable complexity of organisation, 

 and by far the larger number, such as mushrooms, toadstools, 

 and puff-balls are saprophytes, although a few are destructive 

 parasites of forest trees. 



The Common Mushroom {Agariais campestris \,. = Psalliota 



