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



abundant distribution of the uredo form. The dried leaves are covered 

 with black pustules, round to oval, on both sides of the leaf, mostly 

 remaining covered with epidermis, and with the spores firmly adherent. 

 The pustules contained a few uredospores also. The teleutospores are 

 small, much constricted at the septum usually, though the spores vary 

 much in shape, and much thickened at the apex. The fresh spores 

 measured 36 to 44/x in total length, by 14 to 18 in greatest breadth, or 

 10 to 13 at the septum. The thickening at the apex is 6 to 9/*. The 

 spores did not germinate on being put into water, and I therefore 

 conclude that they inquire a winter rest. 



2. PUCCINU ARGENTATA, Schulz. ? 

 On Impatiens amphorata, Edgw. 



In the middle of September I found this host attacked with a 

 brown uredo bearing fungus ; but only in certain localities, and I would 

 characterise it as rare. The upper surfaces of attacked leaves display 

 circular paled patches, and the lower surfaces of these patches bear 

 minute circular brown pustules. Later when the leaf is beginning to 

 wither the invaded areas are conspicuous by their green colour against 

 the yellowed general leaf surface, showing again a lichenoid symbiosis 

 between the chlorophyll cells of the leaf blade and the mycelium of 

 the fungus. A single leaf usually bore immense numbers of these, while 

 the petioles also bore some. Towards the end of September, when the 

 host is beginning to disappear for the season, Puccinia pustules are 

 developed, though uredo pustules are still more numerous ; but gradually 

 the uredo pustules recede. 



The uredospores are brown oval bodies, spiny on the surface, and 

 often displaying a nucleus or nucleolar space, and thus resembling a 

 Uromyces spore (fig. 11, PI. I). They are very deciduous, falling off 

 without any portion of stalk adhering, though the place of union with 

 the stalk is usually clearly definable. The fresh spores measured 24 x 

 16/x on an average. These spores germinated readily in water, throwing 

 out a long simple germ tube, the end being often curiously twisted into 

 an intricate loose knot. Some smaller germ tubes produced a swelling 

 at the end, but this was not separated off by any septum. 



The teleutospores are plump rounded spores, irregular in size and 

 shape, and with little or no constriction at the septum. Most of them 

 display a small conical colourless thickening at the free end ; but some 

 are without this (fig. 11, PL I). The spores are readily detached from 

 their beds, and little or no portion of the stalk adheres. They are deep 

 brown in colour, and the external surface is very faintly tuberculated 

 over both cells. An averaged sized spore measured when fresh 32/x in 



