236 



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



and 7 to 9/n in widtli at the septum. The apical thickening is 6 to 7 /a 

 in depth. 



BemarJcs. — This fungus is probably identical with P. OircmcB, Pars. 

 I only once visited the locality where it occurs, in October, and do not 

 know therefore whether earlier spores of a somewhat different character 

 are formed as is the case with P. Circcere. 



h. Micropuccinia. t 



5. PncciNiA Geeanii silvatici, Karaten. 



on Qemnium nepalense, Sweot. 



During April to June 1 have on several occasions found this 

 plant attacked by a Pwcciwrn-bearing mycelium with this peculiar 

 character that, when it attacks the stem, as it frequently does, it 

 gives rise to very considerable hypertrophy of the host's tissues. The 

 fungus is by no means a common one and usually attacks the loaf blades, 

 distorting and crumpling them (Fig. 10, PI. XII), and forming spore 

 beds in little dark reddish brown pustules on the under surface. A few 

 isolated pustules occasionally open on the upper surface. The pustules 

 are aggregated together in patches of various size, but generally large, 

 sometimes involving half the whole surface of the leaf. On the loaf, 

 the individual pustules are so closely packed together that a superficial 

 examination would induce one to believe that the whole patch is one large 

 spore bed. When the stem or petiole is attacked, the individuality of each 

 pustule is more marked probably because of the hypertrophy always at- 

 tending such cases. In one specimen I found the fungus bad attacked a 

 node of the stem where throe shoots were given off, causing great hyper- 

 trophy (Fig- llj PI- XII) with pale rosy discoloration of the superficial 

 tissues. Petioles were often found attacked and hypertrophiod. Tho 

 pustules on the stem and petioles wei-e often oblong or linear. The my- 

 celium apparently has a distinct preference for invading the vascular tis- | 

 sues because, even when the leaf blade is attacked, it is frequently observed 

 that the mycelium runs mainly along a main nerve, which is then hyper- 

 trophiod, and the space in the angle between two attacked nerves is often 

 filled -with numerous confluent pustules. Tho upper surface of tho leaf, 

 opposite the spore pustules below, is paled and somewhat reddish. ^ 

 Small patches of invasion on the leaf blade are usually convex above, 

 the lower or concave surface bearing the spore beds. 



The spores are brown and powdery very easily detached from their 

 beds with only a small fragment of stalk adhering. Tho upper and lower 

 cells are usually equal in size, and there is little or no constriction at the sep- 

 tum. They are voi'y uniform as a rule in size and shape (Fig. 12, PI, XII). ** 



