84 A. Barclay — A Descriptive List of the Uredineae [No. 2, 



In only one species, namely, that on a species of Salix, do the characters 

 of the teleutospores and uredospores coincide with the descriptions given 

 by "Winter. This would appear to show that the distinctive characters 

 of the uredospore formation in the two genera as usually given, are not 

 of generic value. Lastly, I would draw special attention to the forma- 

 tion of spermogonia in one of these fungi, namely, on Hypericum. So 

 far as I am aware the existence of this form of fructification has never 

 yet been observed in any other species either of Melampsora or of 

 Coleosporium. 



MELAMPSORA, Castagne. 



a. HEMIMELAMPSORA, Schroter. 



1. Melampsora Sancti-Johan^^is, nov. sp. 

 On Hypericum cernuum, Roxb. 



This is a very remarkable parasite, causing very noticable abnor- 

 malities in the host ; for not only are its leaves sometimes covered with 

 conspicuous localised patches of discoloration, but whole shoots are 

 often involved (fig. 3, PI. II). In the latter case the shoot is, before 

 the formation of teleutospores, of a sickly pale yellowish green colour ; 

 often hypertrophied when quite young ; but this hypertrophy is masked 

 later on by arrested growth of the shoot, and the normal shoots of equal 

 age continuing to grow throw^ the attacked shoots out of comparison. 

 The leaves borne by such attacked shoots are always considerably smaller 

 than healthy ones. The fungus in one form or another is to be met 

 with almost throughout the year upon the living host. It is extremely 

 common in this neighbourhood, and plants are often met with completely 

 eaten up with it. The normal course of the fungus through the year 

 is as follows : 



In early spring (March) both the localised leaf patches and wholly 

 involved shoots are abundantly met with ; but the latter are always 

 more abundant than the former. In April some uredo pustules are 

 formed on both localised patches and on the leaves of wholly in- 

 volved shoots ; but much oftener on the latter. These pustules are, 

 however, very uncommon, and must be looked for diligently. I have 

 found them only in April. During the time uredo pustules are formed 

 spermogonia also are found on the same leaves. These are mainly 

 epiphyllous, though a few may be found also on the lower surface. The 

 uredo pustules are minute circular pale yellow sori, mostly hypophyllous. 

 After April there is a cessation of activity in the reproduction of the 

 fungus until July. In this interval, however, if from unusual wet 

 weather new shoots are formed by the host, some of them are found 



