168 
CHARLES B. PLOWRIGHT. 
L. This iEcidium is far from common in Great Britain, but 
in the spring of 1882 I met with it again at Skegness, Lin- 
colnshire. It has been hitherto regarded either as a spore 
form of Puccinia compositarum, Mart., or of P. Sene- 
cionis, Desm. In neither of the above localities was the 
iEcidium accompanied by any Uredo or teleutospores upon 
the same host plant. The North Wootton Station has been 
examined with this point in view repeatedly, and at all seasons 
of the year. Growing in company with the Senecio, both in 
Norfolk and Lincolnshire, was, amongst other plants, Car ex 
arenaria, L. In 1882 I noticed upon this Carex a Puccinia 
occurred on those plants which grew in the vicinity of the 
iEcidium-affected Seneciones, but not elsewhere. A series of 
experimental cultures were consequently undertaken, 1883-4, 
with the object of elucidation of the life-history of the Puc- 
cinia in question. There are, as is already known, several 
■well-marked species of Puccinia which occur upon various 
carices, of these P. carices. Sebum.; P. limosae, Mag.; 
P. sylvaticae, Schrot., and P. dioica Mag., have had their 
life-histories worked out; whereas P. microsora, Korn; 
P. caricicola, Fcke.; and P. vulpina, Schrot. have not. The 
only species with which the Puccinia on P. arenaria can be 
compared is P. dioica, Mag. I therefore sent specimens of 
my plant to Dr. Magnus, -who at once pointed out the difference 
between the teleutospores of the two Puccinia. In P. d i o i c a the 
summits of the teleutospores are not only much more thickened, 
but also generally prolonged upwards into a conical point. 
The uredospores of P. dioica, too, are described by Dr. 
Magnus 1 as being similar to those of P. caricis, Schum. 
Further, Rostrup 2 has, to say the least, pointed out the strong 
presumptive evidence that exists that Puccinia dioica has 
its secidiospores upon Carduus palustris, L.; arvensis, L., 
and lanceolatus, L. It occurred to me that as Puccinia 
caricis, Schum., is our commonest carex infesting Puccinia 
in this country, C. Schoeleriana might only be a variety 
1 Winter, ‘ Rabenhorst’s Kryptogamen Flora,’ 1881, vol. i, p. 182. 
2 llostrup, loc. cit., p. 17 and p. v. 
