464 
PUCCINI A ON GROUNDSEL, 
and the common Groundsel is likely to have some well-known 
rust upon it. Groundsel is an imported weed, probably from 
Britain, and yet curiously enough the very common Groundsel 
rust of the old country ( C oleosporium senecionis, Fries) has not 
yet been met with here. 
In Plo wright's " Monograph of the British Uredineee and 
Ustilagine?e " the following three Puccinias are given as occurring 
on species of Senecio, but none of them on S. vulgaris — 
P. t/lomerata, Grev., (thought to be the typical/ 5 , eocpansa, Link). 
P. senecionis, Lib. 
P. schoeleriana, Plow. &. Mag. 
The two former belong to the Micro-puccinia or those which 
have teleutospores only, and the latter to the Hetero-puccinia, in 
which there are the three kinds of spores, the aecidiospores being 
on one host-plant and the uredospores and teleutospores on a 
different host-plant. Assuming that the complete life-history of 
the above species is known, our fungus belongs to a different 
group, but on the Continent of Europe P. senecionis is known to 
produce aecidiospores as well,* and therefore it might be a similar 
species to ours. But the sori are brown, not black, and that 
excludes it, while on P. glomerate the teleutospores are too small 
for the present species, and the colourless papilla surmounting the 
upper cell is absent from ours. So that there appears to be no 
corresponding fungus on British species of Senecio. 
Turning now to Farlow and Seymour's " Host-Index of the 
Fungi of the United States," the following are given on species of 
Senecio there, and here again S. vulgaris has only the common 
British rust already mentioned : — 
AfCuHum compositarum, Mart. 
A. senecionis, Desm. 
Puccinia conglomerate Schm. & Kze. 
The Puccinias (for there are several) of which A. compositarum, 
is regarded as a stage, belong for the most part to the Iletero- 
* See Dietel in Zeitseh. f. Pflanzenk. Vol. iii. Pt. 5, 259 (1893). 
