1900] CULTURES OF UREDINE IN 1899 a7 1 
species of Euphorbia is not genetically related to the brown rust 
equally abundant upon the same hosts. The evidence I have to 
offer is not conclusive, but, so far as it goes, must change this 
view. On June 20 excidiospores from Euphorbia nutans were 
sown upon two plants of the same species and upon one plant of 
Euphorbia maculata. Nine days afterward uredo appeared upon 
one of the plants of Euphorbia nutans, and in eleven days upon 
' the other, followed in both cases by teleutospores after a time, 
the exact date not recorded, but the plant of £. maculata showed 
no infection. 
Instead of speculating upon such meager data, I am inclined 
to believe that Uromyces Euphorbia is an autcecious species, and 
to await further cultures showing if it is separable into races. 
5. PHRAGMIDIUM SPECIOSUM FY. 
The intimate association of a caeoma, which is not distinguish- 
able from Ceoma miniata Schl., with this exclusively American 
species of Phragmidium, would have been accepted as sufficient 
evidence of its genetic connection, if the same form apparently 
had not been considered in Europe as the first stage of the very 
different Phragmidium mucronatum, a species that is also common 
in this country. 
At the time when the teleutospores of PAr. speciosum were in 
germinating condition no potted plants of native roses were avail- 
able, and sowings were made upon the leaves of a tea rose, the 
Kaiserin Augusta Victoria. The work was done by my assistant, 
Mr. William Stuart, and the dates are not at hand, but in due course 
of time many pustules of caoma appeared. These bore every 
resemblance to the usual form, although they did not become very 
large, which may have been due to the host not being congenial. 
It is probably safe to assume that the rose coma in this 
country belongs wholly to Phragmidium speciosum, or else that 
there are two species not at present separable. 
6. TRipHRaGMium Uxtmariag (Schum.) Lz. 
This Species of rust, not heretofore reported for America, so 
far as the writer knows,-was found in considerable abundance 
