254 PUCCINIA 
scattered or arranged in rows, rarely confluent, minute, more 
or less obloug, pulverulent, orange; spores globose to ovate, 
shortly echinulate, yellow, 16—25 x 14—20y, with three or 
four germ-pores (about ten, Fischer, but ?), and mingled with 
a few paraphyses. 
Teleutospores. Sori hypophyllous, irregularly scattered, 
rarely confluent, oblong or linear, covered by the epidermis, 
soon naked, black; spores cuneate, flat at the summit and 
crowned with about 5—7 obtuse (digitaliform) darker-coloured 
teeth, hardly or not at all constricted, gradually tapering 
towards the base, smooth, brown, 35—60 x 12—22 w; pedicels 
short, rather thick. 
Ecidia on Rhamnus Frangula, May and June; uredo- and 
teleutospores on Agropyron repens, Agrostis alba, A. stolonifera, 
A. vulgaris, Calamagrostis lanceolata, Dactylis glomerata, 
Festuca sylvatica, Holcus lanatus, H. mollis, Phalaris arun- 
dinacea (but not yet recorded on all these grasses in Britain), 
August—October. Common. 
On account of the processes at the summit of the teleutospore this 
species is called Crown Rust. It was surmised by Plowright that there ' 
are two Crown Rusts; these have since been called P. coronatu and 
P. Lolii (=P. coronifera). They are equally widely distributed, but are 
said to occur on different grasses, with the exception that they are both 
found on the two species of Holcus. 
In accordance with custom, they are here kept separate, but aside 
from the distinction of the hosts they can be separated only by minute 
differences. When they occur on Aolcus, therefore, the only test that 
could absolutely decide the matter would be to await the maturation of 
the teleutospores, and then try if they would infect R. Frangula. The 
lighter-orange colour of tne uredo-pustules, and the character of the germ- 
pores will, however, distinguish either of them from P. graminis, when 
occurring on the same hosts; in the Crown Rusts, moreover, both kinds 
of sori are confined almost entirely to the leaves. 
The teleuto-sori of P. coronata have a less decided tendency to group 
themselves round the uredo-sori than in P. Loli, and do not remain so 
long covered by the epidermis, becoming naked early in the autumn. In 
the uredo-sori, Eriksson says that paraphyses occur in P. coronata and 
hardly at all in P. Loli ; but the evidence seems to favour the conclusion, 
in general, that the presence or absence of paraphyses is a note of little 
importance. Plowright mentions an interesting fact, confirmed by Pole- 
Evans, that the Crown Rust, when it occurs on Dactylis, is au early summer 
