Indigenous Species with their Hosts. 49 



It is worthy of remark that on some of our most predominant families, 

 such as Myrtaceae and Proteaceae, which are only exceeded by the Legu- 

 minosae, the rusts are practically absent. It is passing strange that upon 

 our numerous Eucalypts and kindred species not a single rust-fungus 

 should have developed, while in the Proteaceae, with their wonderful variety 

 of foliage, only a single species, and that a Uredo, is recorded. Melamp- 

 sora eucalypti Rabh. found in Calcutta on the leaves of Eucalyptus globulus 

 is merely a name, and the specimens show no indications of a rust. I have 

 carefully examined the original specimen in Rabenhorst's Fungi europaei 

 2592, and while the leaves have numerous blister-like swellings over them, 

 they are found to consist of discoloured cells, the epidermal cells parti- 

 cularly being brown and discoloured, and might superficially be mistaken 

 for spores. 



In the preceding table only indigenous rusts are given which occur on 

 native host -pi ants, but such rusts may either be confined exclusively to 

 native planits or they may occur on other allied introduced plants growing 

 here as well. Thus Puccinia tasmanica is found on the introduced weed 

 the common groundsel (Senccio vulgaris), but one stage of it is also found 

 on native species of the same genus, and, therefore, it is regarded as in- 

 digenous. The rust may also be found on native plants, though in other 

 parts of the world on allied species, and yet be regarded as native, as 

 in the case of P. perplexans and P. agropyri. There are even cases 

 where native rusts, or at least rusts not known elsewhere, are confined 

 exclusively to imported plants, as P. calendulae, P. cinerariae, and P. 

 distincta. As regards introduced rusts, they may be found on both 

 native and imported plants, the presumption being ithat the rust spread 

 from one to the other, though some may incline to the view that these are 

 as much natives of Australia as of any other country. Disregarding 

 Puccima graminis, there are four such species, P. menthae, P. malvace- 

 arum, P. thuemeni, and Melampsora lini. There is still another group 

 consisting of introduced rusts found here on imported plants alone, siuch as 

 Puccinia chrysanthemi and Phragmidium subcorticium. 



