100 

The generally accepted view as to the means by which the Ustilaginez 
infect their host-plant is, that the parasite gains admission into the 
_ embryo, soon after the seed has germinated. This is the case with 
! Tilletia tritici, Ustilago avene, Ustilago nuda, gen and is indeed 
generally true. But it is not the way by which all species of Ustilago 
\ vafect their hosts. For example I have long held the opinion, 
founded on certain experiments made some years ago, that U. violacea 
i on the anthers of Lychnis disica infected its host by the agency of 
i insects, especially bees, which carried the spores directly from an infected, 
toa sound flower. During the month of June last, I transplanted a 
vigorous young plant of L. dioica affected with the Ustilago froma wood 
at East Winch, near King’s Lynn, into my garden, and planted it in 
close proximity to a healthy plant of the same species which had been 
growing there since spring. [he transplanted specimen survived the 
process of removal and produced a succession of smutted blooms. 
Towards autumn the healthy plant began to produce a few smutted 
blossoms, the majority of which were on the side nearest the diseased 
plant. Some of these blossoms I now exhibit. Someare healthy, some 
bear the Ustilago in their anthers and one branch has blossoms of both 
kinds.* This, I take it, conclusively demonstrates the truth of my 
contention that U. violacea does not enter the embryonic plant and 
grow upwards with it as many of the Ustilaginee do, but that it is 
implanted directly into the inflorescence by insect agency. 
UREDINEZ.  Tulasne. 
UROMYCES Link. Uromyces parnassiz (D.C.) 
salicorniz (D.C.) 
I. Euuromyces. Schroter. Heteruromyces. 
Auteuuromyces. Uromyces dactylidis. Otth. 
Uromyces fabz (Pers.) poz Rabh. 
orobi (Pers.) 
phaseoli (Pers.) 
limonii (D. C.) 
lineatus (Desm.) 
= fic. glaucis 
junci (Desm.) 


| polygoni (Pers.) pisi (Pers.) ? 
| trifolii (Alb. and 
| Schw.) II. BracHyuromycts. Schrot. 
| eranii (D. C. 
' a ors) ) III. Hemiuromyces. Schrot. 
a valerianz Uromyces scutellatus (Schrank) — 
a (Schum.) anthyllidis. (Grev.) | 
| i chenopodii Duby rumicis (Schum.) 
ected 
* During the following Spring, 1900, both plants produced nothing but 
smutted flowers. 
occa 
= 
tS a Se 
: 4 
Ti ee ih ces 
te. 3 

