Arthur: Cultures of Uredineae 
81 
on Carex vulpinoidea, at Leland, Mich., Aug. 26, 1913, was used 
to sow April 2, on Solidago canadensis and Aster paniculatns. 
Abundant infection occurred on the Solidago, pycnia showing 
April II, and aecia April 20, but the Aster remained free. The 
collectors found in many instances old aecia on S. canadensis in 
the field, intermixed with rusted Carex vulpinoidea. The infer- 
ence from field observation, and also the cultural work of last 
year as recorded above under number 15, is confirmed by the 
culture. 
A collection of P. Dulichii Syd., on Dulichium arundinaceum, 
gathered Jan. 17, 1914, at Gainesville, Fla., by Mr. H. E. Stevens, 
was accompanied by young aecia on a species of Aster. This 
association suggested that they might be genetically connected. A 
sowing from the Dulichium material was made, Jan. 22, on Aster 
Drummondii, A. paniculatus, and on an undetermined Aster, 
which had been obtained from a field near New Orleans, La., 
also on Solidago canadensis and Senecio obovatus. Another sow- 
ing from the same material was made, Jan. 31, on the same three 
species of Aster, and on A. Tzueedyi. The only infection was a 
sparing production of pycnia on Solidago canadensis, showing 
Feb. 3, which did not continue into aecia. As soon as this result 
was noticed, another sowing from the same material was made, 
Feb. 4, on Solidago canadensis, which resulted in an abundant in- 
fection, showing pycnia Feb. 16, and aecia Feb. 25. From this 
result, together with a careful microscopic study of herbarium ma- 
terial, it is inferred that P. Didichii is a part of the common P. 
extensicola, although the telial host is not a Carex. It is the first 
time that any Carex rust has been traced to a telial host outside of 
the genus Carex. 
20. PucciNiA TOSTA Arth. — A collection was made by Dr. 
Fromme and the writer at Mesilla Park, N. Mex., on what was 
thought at the time to be Muhlenbergia Porteri, but which later 
proved to be the very similar appearing Sporobolus asperifolius. 
Thinking that it was P. Muhlenbergiae, known to have its aecia 
on malvaceous hosts, it was sown, March 20, on Callirhoe invol- 
ucrata, C. digitata, and Sphaeralcea incana. Infection was ob- 
tained only on the last host, pycnia showing March 27, and aecia 
April 3, both in great profusion. Another sowing was at once 
