2^ DtSSEMINATIDN OV PARASITIC FUNGI 



P. furimrea on sorgliiun. 



P. Thuemeni on ccloiy. 



Two aie (jii grasses inipoited l)y the Department of Agriculture, 



Victoria, from the United States, in ]903. the rusts first 



appearing in December to March, ] 903-1901. 

 P. Lnpatinilis on Ehjnius condensaius. 

 P. Bechn((i>iiiw on Bechnconna eruccBjormis. 

 Three arc on field grasses and probably came with the seeds of their 



liosts, in grass packing, or were introduced by settlers. 

 P. AnthoxcDifhi on Antlioxanlhus odore/inn (sweet vernal grass). 

 P. FestHcw on Feduca ovina and P. rigida (fescues). 

 P. poarum on Poa annua. 

 One {P. Cj/ani on cornflower) is on a garden flower and field weed and 



was probably introduced ))y florists, but may have come in 



packing. 

 One {P. Arenarice on chick-weed) ])r()])ably came witli the seeds of its 



liost in packing. 

 While two are doubtful, P. Ptenaidhes on Lacluca sp. ai\d P. 



Hypochoeridis on Hypochoeris radicata and H. glabra. 

 The genus Uiomyces is the second largest Australian genus of the 



rusts. Dietel^ says that of the 31 species recordf^d up to 1911, 



five have been introduced. 

 U. Fabce on beans (Vicia Faba). 

 U. apjjendiculatus on cowpea. 

 U. Betce on beet and mangel. 

 U. mryopliyllinus on carnations. 

 U. Trifolii-repentis on clover. 

 These are all on cultivated plants whose introduction can be leadily 



understood. IMcAlpine gives U. Polygoni on knot-Aveed as 



well, and thinks tliis niight easily be carried with the seeds in 



straw-]mcking or in hay. More recently^ U. striafus on lucerne 



has been found and doubtless came in with imported seed from 



Europe or America. 



To sum up this discussion of the three principal metliods by which the 

 " discontinuous spread " of parasitic fungi, which rely on spores for their 

 transmission, may be effected, the evidence available from cases sufficiently 



1 Ann. Mycol IX, 1911, p. 160. 



2 Second Report, Bureau of Microbiology, N. S. W., 1912. 



