442 NOTES ON UROMYCES AMVGDALI, COOKE, 



In order to make sure that we were dealing with the same 

 fungus, I have examined peach leaves with the fungus named V)y 

 Cooke himself in the Herbarium of the Government Botanist, 

 and there is no doubt as to the identity of the specimens. 

 Further, JNIr. Trj^on has ver}^ courteously sent me specimens of 

 peach leaves similar to those formerly submitted to Dr. Cooke, 

 and on which the name was based, with this important difference, 

 however, that the original specimens were collected in February, 

 while these are dated June. 



In addition to this, specimens on peach, plum, apricot and 

 almond leaves had been sent from South Australia to the United 

 States Division of Vegetable Pathology, and it was reported in 

 the Journal of Mycology for 1890 that these specimens agree in 

 every particular with those of Puccinia pinmi, Pers., on peach 

 and i^lum hosts in the United States, nevertheless his own name 

 was still retained by Dr. Cooke. 



As the leaf-rust is unfortunatel}^ becoming, or rather has 

 become, very prevalent and a very serious pest to the fruit- 

 grower, it is at least advisable to agree upon some common name, 

 to have uniformity of nomenclature in the different Colonies, so 

 that when dealing with it therapeutically we may be agreed as to 

 the cause of the disease dealt with. And not only so, but the 

 name here has an important bearing when it enables us to 

 recognise the useful fact that the rust in our orchards and the 

 rust in our wheat-fields are but different species of the same 

 genus (Puccinia), and that whatever prevents the disease in the 

 one case is likely to be efficient in the other. 



A further necessity exists for accurate scientific determination 

 of this fungus from the fact that it is very commonly called 

 " Peach Yellows " on account of the yellow blotches or freckles on 

 the upper surface of the leaf, but it has no connection with the 

 dreaded American disease so-called, which is believed to be, after 

 years of investigation, due to Bacteria. 



In the plum the spots assume a much darker colour, and the 

 numerous pustules on the undersurface of the leaf sometimes 

 give it the appearance of being coated with brown mud. 



