122 UROMYCES 
On Allium Schoenoprasum, A. Scorodoprasum, and (ac- 
cording to Sydow) A. sphaerocephalum. Not common. (Fig. 73.) 
It cannot be considered as certain that this is a species distinct from 
Puccinia Porrt Wint., but as it presents slight differences, it is better, in 
the total absence of culture experiments, to keep it separate for the time. 
The difficulty lies in the fact that the teleutospores of this Uromyces agree 
perfectly with the mesospores of the Puccznia (except perhaps in the greater 
variability of the latter) ; but the teleuto-sori of the Uromyces are generally 
larger and more persistently covered by the epidermis, and one searches 
in vain in them for two-celled spores, such as are found freely in the sori 
of the Puccinia. Fischer says that the uredospores of P. Porri have only 
three germ-pores. According to Sydow, the Uromyces occurs only on the 
three species of Allium mentioned above and A. rotundum, while the 
Puccinia is found on them as well as on many other species of the genus. 
Nevertheless the two forms are closely allied and from the evolutionary 
point of view the Uromyces must be regarded as a specialised state or 
mutation of the Puccinia. Neither of them has an ecidial stage. 
DisTRIBUTION: Central and North-Western Europe. 
34. Uromyces Colchici Massee. 
U. Colchici Mass. Grevillea, xxi. 6, pl. 182, f. 16—18; Diseases of 
Cult. Plants, p. 292, f. 85; Text-book of Plant Diseases, p. 227, 
f. 56. Sydow, Monogr. ii. 268. 
Teleutospores. Sori amphigenous, scattered, rather large, 
elliptical, sometimes circinating, up to 2mm. long, 
covered for some time by the epidermis which at 
length splits, then sub-pulverulent, brown ; spores 
subglobose to ovate, rounded above, with a broad 
flat hyaline papilla, smooth, pale-brown, 28—40 x 
Fig. 74. U. 20—28y; epispore 3—34 u thick; pedicels hya- 
Colchici. — line, rather long, but very deciduous. 
Teleutospore, . ’ 
from the ori- On leaves of Colchicum speciosum. Kew 
ea specl- Gardens; unknown in the world elsewhere. 
(Fig. 74.) 
The teleutospores remain on the dead leaves and germinate in the 
following spring, so that if Colchicum is again planted in the same ground 
or allowed to remain there, it is liable to contract the disease year after 
year. As in all similar cases, the best preventive against future attacks 
