CERTAIN BRITISH HETERCECISHAL UREDINES. 
169 
of it occurring upon C. arenaria. The following duplicated 
cultures were therefore made. 
a. A quantity of P. Schoeleriana was germinated in water 
in a watch-glass. This was divided into two parts, one of which 
was applied to a young plant of Senecio J acobaea (260), and 
the other to a plant of Urtica dioica (261). The Senecio 
became affected with the iEcidium, but the Urtica did not. 
b. Conversely, a quantity of P. caricis was germinated in 
water in a watch-glass, and divided into two parts, one of 
which was placed on a plant of Urtica dioica (258), and the 
other upon a Senecio (259). The Urtica became affected 
with the iEcidium, the Senecio did not. The spores of 
JEcidium Jacobsese applied to Carex arenaria gave rise 
to theUredo (199, 888, 389). The teleutospores of Puccinia 
Schoeleriana in seven separate cultures in every instance 
produced the iEcidium upon Senecio Jacobaea (260, 285, 
291, 292, 293, 294, 447). 
The Puccinia in question it is proposed to call Schoeleriana 
after Schoeler, 1 the Danish schoolmaster, who lived at the 
beginning of the present century in the village of Hammel, 
near Aarhuus, where he, by careful observation of what hap- 
pened in nature, came to the conclusion that the yellow fungus 
on barberry has some connection with the rust on oats. He 
began these investigations in 1807, and continued them for 
some years. 
In 1816 Schoeler applied the “yellow dust” of the barberry 
fungus to some healthy rye plants, which were still moist with 
dew, and found the latter had, in the course of some few days, 
become badly affected with rust; “while at the same time not 
one rusty plant could be found anywhere else in the whole rye 
field.” Schoeler was also aware of the fact that rye became 
affected with rust without the intervention of the barberry. 
1 Shoeler, “ Berberissens Skudelige Indflydelse pa Sseden,” ‘ Landaekom- 
miske Tideuder,’ 1818, part viii, p. 289* 
