Physiology of the Genus Eidamia . 405 
m 4 v 
results are likely to vary with the use of distilled water or conductivity water 
and according to the degree of purity of the chemicals themselves. 
In both E. cateimlata and E. viridescens the maximum growth occurs 
in N/5 or N/10 solutions. In the case of E. viridescens growth is con¬ 
siderably retarded in molar solutions, but in E. cateimlata the retardation is 
not strongly marked. 
In the case of E. viridescens , odour was present in every member of 
each series, being strongest in the fifth molar member. Whilst practically 
no difference could be detected between the glucose and lactose series the 
odour was appreciably less in the sucrose series. With regard to sporing, 
after four days no sporing was evident in the unimolar cultures: in the 
remaining cultures very little difference in the amount of sporing was 
manifest. The sporing is confined to a zone about 15 to 17 mm. wide in the 
peripheral region of the colony. After a longer period of time the colour of 
the spore masses in unimolar glucose varied from white to pale olivine, 
passing to dark yellowish green and dark green in N/50 and bottle-green in 
N/100, with the central region of the plate free from spores : in lactose the 
colour varied from pale olivine to French green in N/5 and N/io, changing 
to Empire green in N/100, whilst in sucrose the colour ranged from French 
green to Danube green. 
In the case of E. cateimlata there was little colour variation in the 
spore masses (relatively more numerous in N/5 cultures) throughout the 
series ; the colour varied from cream-buff to chamois, whereas in agar alone 
it was avellaneous. 
2. Starch. 
The ability of the species of Eidamia to hydrolyse starch was tested by 
the method employed by George L. Peltier ( 14 ). Peltier applied a solution 
of iodine in potassium iodide to the surface of starch-containing media con¬ 
taining growths of Pseudomonas citri , and found that the colonies of P. citri 
remained yellow, whilst the surrounding medium was coloured dark blue. 
Each colony was surrounded by a narrow, clear, starch-depleted zone : this 
was followed by a reddish-brown band indicating erythrodextrin, an inter¬ 
mediate product, which merged into a bright blue band and finally into the 
dark blue colour of the starch-containing agar. This method has been in 
use for some time by the first-named writer as an aid to the specific deter¬ 
mination of fungi, since fungi often show well-marked differences in the effect 
produced upon irrigation with iodine, related chiefly to the width of the 
coloured and uncoloured zones and the intensity of the colours present in 
the region where partial hydrolysis exists. Various starch-containing media 
were used for this purpose, notably potato extract agar with or without 
various organic acids and synthetic nutrient media of different kinds. In 
the case of Eidamia acremonioides no evidence indicating starch hydrolysis 
