in the Bromes and their Brown Rnst. 257 
1 6--1 7 mm., the purplish f seeds’ remaining adherent in the 
spikelet, &c., as before. Perhaps the ‘ seed ’ is a trifle more 
pubescent, but I can detect no essential difference. 
B. ciliaris germinated freely, seventeen out of nineteen 
sown having come up well in five days. 
4. The Germination of the Bromes. 
It was necessary, at a certain stage in the experiments, to 
obtain some information as to the germinating capacity — in 
the sense in which this term is used by nurserymen and 
experts — of the ‘ seeds.’ 
To do this I employed ordinary Petri-dishes, with a filter- 
paper above and below, and sowed the c seeds ’ on the lower 
paper. When the first root-hairs 1 form, the seed becomes 
firmly adherent to the paper, and many advantages can be 
taken of this fact. For instance, it is easy to lift the ger- 
minating seedling up with forceps, by tearing the wet paper, 
and so transfer the whole bodily to a tube, &c. ; and since the 
radicle rapidly pierces the paper in many cases, this pro- 
cedure often obviates any rupture of the delicate roots and 
root-hairs. 
Such seedlings in dishes are extremely geotropic and helio- 
tropic, and it is easy to take advantage of this fact when 
infecting the first leaf of the plumule. If the Petri-dish is 
left flat, the green leaf curves up and soon presses against 
the lid, and if spores are sown on the leaf the film of water 
between leaf and lid is of advantage in the germination of 
the spores. In obtaining infected leaves for hardening and 
subsequent section-cutting it is useful to have the seedlings 
quite straight. This is easily done by laying the s seeds ’ with 
their axes parallel and apices all turned one way. As soon 
as the radicle begins to emerge, and the first root-hairs have 
fixed the seedling, the whole dish can be placed vertically on 
its edges, and so illuminated that root and shoot grow out in 
one straight line — -the axis of the ‘ seed.’ The plumule can 
1 These first hairs would be more properly described as anchoring-hairs ; they 
are developed not from the root but from the coleorhiza surrounding it. 
