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Williamson .— The Origin of ‘ Golden Oak. 
From the fact that E. catennlata is the fungus produced from the 
original specimen of golden oak after careful external sterilization, and that 
oak inoculated with this fungus becomes the same golden colour as the 
original specimen, it can be concluded that the golden colour in oak is caused 
by Eidamia catennlata. The other fungi found on the original specimen 
are growing externally only. This conclusion is confirmed by an examina¬ 
tion of sections of the original oak and artificially infected oak. 
A few other woods, such as chestnut, beech, were inoculated in the same 
way with this fungus. The effect on beech is to darken somewhat the 
colour of the wood, whereas the chestnut becomes a marked golden colour. 
Morphology of Eidamia catenulata. 
The morphology of this fungus is fully described in the paper dealing 
with the genus Eidamia ( 4 ). It may be summarized here as follows : 
(i) The mycelium is composed of septate branched hyphae, varying in size 
from 3 fjL to io /x in width, and having thin or thick walls according to the 
medium supplied. (2) Two types of spores occur, conidia which are yellow 
in colour and hyaline spores. (3) The conidia are narrow to broadly 
elliptical, pointed at both ends, and vary in size from 4 by 2 ju to 7 by 3-5 p. 
There may be as many as 100 in one chain, and balling of the spores may 
occur. (4) The conidia are borne on sterigmata which are slender, slightly 
swollen at the base, and vary in size from 8-16 /x in length and 1-2-5 P * n 
width at the base. (5) The sterigmata may be borne singly on a hypha or 
on a short branch or a number at the head of a slightly swollen branch, or 
a Penicillium type of conidiophore may occur. (6) The hyaline spores are 
borne directly on the hypha or at the end of a branch or may be intercalary. 
They are round or slightly pear-shaped, with fairly thick walls, and vary in 
size from 7-5 by 8*5 p, to 14 by 10 p or 18 fi diameter. (7) The colour of the 
culture varies from pale cream, old gold, to cinnamon brown, according to the 
medium used, the age of growth, and the temperature of incubation. 
Physiological Characteristics of Eidamia catenulata. 
Details of the experiments on the physiology of this fungus are given 
in the paper dealing with the genus Eidamia , and may be briefly summarized 
here. (1) E. catenulata is capable of hydrolysing starch, and grows on 
soluble pectin. (2) This fungus can grow on various sugars such as glucose, 
lactose, maltose, galactose, fructose, mannose, and sucrose, and it causes an 
appreciable inversion of cane sugar. (3) A moderate growth is obtained on 
peptone, which becomes considerable when glucose is added to the peptone. 
(4) Asparagin can be used by the fungus as a source of nitrogen only in the 
presence of mineral salts, and ammonia is liberated. (5) E. catenulata is 
highly tolerant of acids, being able to grow at a hydrogen-ion concentration 
