121 
w observations were made with a view to ascertaining 
what factors condition the orientation of the pycnidium, for 
the latter in early stages of its development is isodiametrical. 
Two plate cultures were supported on their edges so that the 
other plate received it from above on their potential ostiolar 
sides. The face of each plate remote from the ight was ren- 
dered opaque. The development of the pycnidia in both cases 
was perfectly normal, the ostiole being away from the nutrient 
substratum. : 
hyphae from the wall grew out into the tire ee. focd layer. 
isturbed, no 
, and in many cases the wall was 
quite irregularly burst to allow of the exit of the spores. In 
other cases no opening of any kind was formed. 
n a very thin film of nutrient material was poured over 
a plate containing developing pycnidia or the added layer was 
very frothy from violent shaking the disturbing effect, although 
still apparent, was not nearly so well marked. | : 
_ These observations, though somewhat primitive and incon- 
clusive, would appear to indicate that relation to food supply, 
and not light or aeration, is the primary factor conditioning 
the orientation of the pycnidium. 
Infection Experiments.—Infection experiments were carried 
out on Lavandula officinalis, using pure cultures of the fungus 
grown on lavender gelatine. The results of this work are sum- 
marised below. 
Experimental Infections on Lavandula officinalis. 
First Distinct Signs | al, 
es. | Apert. of Biections — 
SU | 
1. Suspension of | Pycnospore | On 11 shoots in 9-10) Pycnidial formation in about 
Spores in sterile! days. 31 days. 
Water brushe | On 1 shoot in 15 days a. 
on the surface of Hyaline On 10 shoots in 10-11) Pycnidial formation in about 
12 shoots. | “Conidium. ays. 37 days. 
On 2 shoots in 17 days 
| Brown None after 30 days ...| None. 
Conidium. 
Chlamydo- | None after 30 days “| None. 
re. 
