ON VIOLA 208 
On Viola cornuta, V. lutea, V. tricolor, and most of the 
many hybrid Violas and Pansies now cultivated in gardens. 
Fresh ecidia are formed right through the summer till August, 
while those of P. Violae cannot usually be found after early 
June. (Fig. 150.) 
The mycelium of the ecidia is perennial in the underground parts ; all 
the shoots which arise from the affected plant are deformed, the internodes 
are lengthened, the leaves become smaller, paler and often twisted. In 
P. Violae this is not the case; only a slight swelling arises at the part 
where the localised mycelium is producing its wxcidia. Bock (Centralbl. 
fiir Bakt. 2. xx. 586) found that he could produce the ecidia of P. Violae 
on the three species of Viola named above, by artificial infection ; but like 
others he still considered the two species as distinct on account of their 
different habit. Liro, on the contrary, considers them as the same. In 
my experience, the uredo- and teleuto-sori of P, aegra are larger, and 
remain longer covered by the epidermis, but the spores are identical. 
This species can do considerable harm if allowed to spread ; there is 
no remedy, but all infected plants should be carefully uprooted and burnt. 
A Viola, badly attacked by the ecidium, was once sent to the Gardener’s 
Chronicle by a correspondent as “a hybrid between a fern and a violet.” 
DISTRIBUTION : Germany, Denmark. 
75. Puccinia Fergussoni B. et Br. 
Puccinia Fergussoni Berk. et Br. Ann. Nat. Hist. 1875, p. 35. Cooke, 
Grevillea, iii. 179, pl. 49, f. 10 ¢; Micr. Fung. p. 210. Plowr. 
Ured. p. 207. Sacc. Syll. vii. 682. Sydow, Monogr. i. 444. Grove, 
Journ. Bot. 1912, p. 10. 
Teleutospores. Sori hypophyllous or on the petioles, on 
large roundish or irregular yellow spots, 
in suborbicular or (on the petioles) elon- 
gated clusters up to 14 em. long, densely 
crowded and confluent, long covered by \) 
the epidermis, then pulverulent, choco- 
late-brown; spores irregular, generally \ 
oblong, attenuated or rarely rounded at fig.151. P. Fergussoni. 
both ends, thickened above in a conical poner all and me- 
form (up to 6 ,), gently constricted, 
smooth, pale-brown, 26—45 x 12—18 yw; pedicels hyaline, thin, 
deciduous, up to 30 w long; an occasional mesospore is found. 
