43 



nas been said that the injury caused by spring rust and mildew 

 is inconsiderable, this is by no means borne out by facts. Com 

 plants badly infected by it have been carefully watched, and 

 have been found to yield poor crops of more or less shrivelled 

 grains. In some cases where wheat has been much covered with 

 the blotches of the fungus, the plant appeared to be quite checked 

 in its growth. 



With respect to the hibernation of this fungus, Puccinia rubigo 

 vera, there is some doubt. De Bary has proved that the teleuto- 

 spores will germinate readily, and form ^Ecidia upon some 

 species of the Boraginacea, as Borago officinalis, common 

 borage, Anchusq officinalis, common alkanet, and other 

 species in the autumn, in this respect differing from those of 

 Puccinia graminis, which will not germinate until the spring. 

 De Bary first proved this, and termed this form JEcidium 

 asperifolii. He also found that the spores from this ^Ecidium 

 form germinate upon grasses and corn plants in the same way as 

 the spores from JEtidium berberidis* But De Bary shows that 

 the spring rust is reproduced year after year in frightful quantities 

 by the uredo spores only. These produce also millions of teleuto- 

 spores which germinate, but without result, because the sporidae 

 seldom meet with the conditions necessary for developing 

 aecidia. These certainly are developed if the conditions are 

 favourable ; but the instance shows that the species can multiply 

 abundantly without the interposition of aecidia.f 



The fungus causing spring rust and mildew is continued 

 through the winter in the uredo form upon grasses and self- 

 sown corn plants, and probably upon winter wheat and winter 

 barley. Frank, confirming De Bary's statement as to the 

 fungus passing the winter in the uredo form upon self- 

 sown corn plants and grasses, says that it is most desirable 

 to eradicate wild grasses from the neighbourhood of corn fields, 

 and especially Bromus mo His, soft brome grass. He also 

 advises that all weeds of species of Boraginece should be 

 rooted up. J 



Puccinia rubigo vera is most common in India. Mr. 

 Barclay remarks that " P. rubigo appears to be the most pre- 

 valent rust in the Simla region." The natives of India 

 recognise the distinction between Puccinia rubigo vera and 

 Puccinia graminis. They call the first " Rolli," and the other 

 " Rolla." 



In America Puccinia rubigo vera is also quite common, 

 according to Mr. Galloway, Chief of the Section of Vegetable 

 Pathology of the United States Department of Agriculture. 



In Australasia it is extraordinarily abundant. At the Rust 

 Conference in New South Wales, before alluded to, Dr. Cobb 



e Monatsbericht der Akademie der Wissenschaften, zu Berlin, 1866. 

 f Comparative Morphology aiul Biology of the Fungi ; Mycetozoa and 

 Bacteria, by A. De Bary 1884. 



t Die Krankheiten der Pjianzen. Von Dr. A. B. Frank. 



Rust and Mildew in India. By the late A. Barclay, M.B., F.L.S. 



