X887.] in the Neighbourhood of Simla. 367 



such places being about 0*441 m.m., wbilst the normal thickness is about 

 0-239 m.m. 



A little later, towards the end of May, when the secidial parasite is 

 becoming rare, some of the compound leaves (never the simple ones) 

 may be found attacked by a separate mycelium bearing uredospores. 

 This uredospore-bearing mycelium is never found on the same leaf 

 bearing secidiospores, and it is therefore quite probable that the two 

 mycelia are in no wise genetically related to one another. The uredo- 

 pustules are minute, circular, and saffron-coloured, mostly on the upper 

 surface of the leaf, though by no means infrequently also on the lower. 

 Sometimes the upper surface of a leaf may be seen to be densely covered 

 with these uredo-pustules. 



Again in autumn, about the end of September and October, the 

 same plant may be seen largely affected by a puccinia-bearing fungus, 

 a distinct interval having elapsed since the disappearance of all trace 

 of the uredo-bearing fungus. These puccinia-pustules are minute and 

 round, like the uredo-pustules, but black, and occur both on the upper and 

 lower surfaces of the leaves, sometimes in great profusion. The stem 

 is also often affected ; the pustules here are linear, their long axes 

 porresponding with the long axis of the stem. 



The oecidiospores are reddish yellow with very thin walls, the 

 epispore and endospore not being distinguishable from one another : 

 they are round, oval, or somewhat fusiform (Fig. 14, PI. XXL). The round 

 spores measure 20 to 21 //, in diam., the oval about 32 x 20 /x, and the 

 fusiform about 38 X 14 /u,, shortly after being wetted with water. 



The spermogonia are likewise situated on the under surface of the 

 leaf : they measure about 0*163 m.m. in depth and 0.189 m.m. in 

 breadth. Their mouths are beset with paraphyses projecting about 

 0.063 m.m. The spermatia are round or oval and measure 4 x 3 /x. 



The peridium consists of elongated cells, very unlike those of the 

 aecidium on Sanicula described above, measuring about 60 x 20 /x, and 

 easily detached from one another by teasing (Fig. 15, PI. XII.). 



Uredospores. — These are reddish yellow round or oval bodies with 

 coarse tubercles on the surface of the epispore. On an average, the 

 moistened spores measure 22 x 18*3 /x. They germinate readily in 

 water. (Fig. 3, PI. XII.). 



Teleutospores. — These are brown two-celled bodies (puccinia) readi- 

 ly detached from their beds with a very small portion of the stalk re- 

 maining adherent to them. In each cell, a clear nuclear body or space 

 may be seen. The epispore is marked externally by fine ridges. They 

 are not thickened at their free ends. As with the uredospores, I never 

 succeeded in getting them to germinate in water. Their measurements 

 46 



