546 
G. R. BISBY 
Species. Such variations as occur are considered in the discussion of 
the races. 
The telia and tehospores show the greatest variation. It has been 
chiefly upon tehospore characters that specific differences have been 
previously indicated. Some teha are pulverulent, some more compact. 
There is considerable variation as to size of telia. The teliospores, in 
some collections and upon some species of host, are somewhat verru- 
cose; the apical thickening, the size, the pedicel length, and in a meas- 
ure, the color, likewise vary. While these variations are not altogether 
constant, some of them can be made use of in separating races, as is 
indicated later. 
Holway (N. Amer. Ured. i : 76) points out that Puccinia Epilobii- 
tetragoni shows a tendency to produce only aecia and telia at higher 
altitudes. This is a condition that has been previously observed with 
rusts. (See Magnus^ and Fischer,^ and further data under Puccinia 
Epilobii-Fleischeri.) 
Intermingling of the perennial mycelium producing aecia and the 
local mycelium producing uredinia and telia, is frequently evidenced. 
So too, cases are found in which local gametophytic and sporophytic 
mycelia are intermingled, pycnia, aecia, and uredinia or telia or both, 
being sometimes found close together upon the same leaf. This point 
affords an opportunity for further study. 
South American, European, and other foreign collections of this 
rust, upon Epilobium, as represented in the Arthur herbarium, show 
no morphological characters different from those of North American 
collections. 
From the data at hand, as previously indicated, it appears that 
Puccinia Epilobii-tetragoni is a very variable species; these variations 
can be made use of in assigning morphological races to this species. 
To Mr. C. A. Ludwig thanks are due for a certain amount of the 
preliminary work pertaining to the separation of these races. The 
races are, in general, as follows: 
I. Puccinia Gayophyti race. This race occurs upon Gayophytum 
(Puccinia Gayophyti) and Chamaenerion and Epilobium (P. Epilobii- 
tetragoni, P. pulverulenta, P. intermedia). The hosts of this race are 
very similar as to vegetative characters; so too are the forms of this 
8 Magnus, P., Bericht. Deutsch. Bot. Ges. 11: 453-464. 1893, and Hedw. Beibl. 
39: 147-150. 1900. 
^ Fischer, Ed., Verb. Schweiz Nat. Ges, Luzern 88: 47. 1906. 
