3 6 4 
Bancroft.—Researches on the 
The action of different media was tried for the purpose of ascertaining 
whether the composition of the medium in which germination took place 
would have any effect on the production of conidia of Hormodendron. The 
following media were employed :— 
1. Distilled water. 
2. A solution of mineral salts in water consisting of equal weights 
of potassium phosphate, calcium chloride, and magnesium sulphate, and 
amounting to 2 per cent, total salts. 
3. A 2 per cent, solution of pure cane sugar. 
4. A decoction of dried leaves of Catalpa and Cabbage made by 
grinding the leaves in a mortar with the addition of a little water, filtering 
through muslin and adding more water to make up to a 4 per cent, solution 
of the expressed juice of the leaves. In these media the germination of 
conidia of Cladosporium taken from leaves of Cabbage, Catalpa , Oak, and 
Funkia was carried out in ‘ hanging-drops It was found that whatever 
medium was employed the same result attended the germination of the 
conidia, viz. the formation of conidia of Hormodendron. 
The conidiophores and the small masses of cells produced by the 
mycelium of Cladosporium were also found to be capable of giving rise 
to conidia of Hormodendron. When some of the conidiophores of Clado¬ 
sporium were mounted in a ‘ hanging-drop ’ in a 2 per cent, solution of cane 
sugar it was found that occasionally from the broken end of a conidiophore 
there arose a hypha which branched, and at the tips of the branches were 
borne conidia of Hormodendron. The small masses of cells produced by 
the mycelium of Cladosporium were also found to be capable of giving rise 
to hyphae which bore conidia of Hormodendron. 
These experiments showed that not only can conidia of Hor7nodendro7i 
be produced by Cladosporium> but also that there is a great tendency on the 
part of Cladosporium to give rise to conidia of Hormodendron , and that this 
tendency has made itself manifest, in the case of the species of plants used 
as the source of Cladosporium , independently of the nutrient medium 
employed for germination. 
By making use of the method described above for the preparation of 
a pure culture, it was found possible to obtain a pure culture of Cladosporium. 
The medium used consisted of 4 per cent, of the extracted juice of fresh 
grapes and 6 per cent, of gelatine. In the pure culture the growth and 
development of the mycelium were followed. The hyphae were at first 
colourless and became later olive in colour. The general nature and 
appearance of the mycelium and of its component hyphae were similar 
to those of the mycelium and hyphae in the cultures of Hormodendron 
described above. From the hyphae there arose lateral branches which 
grew above the surface of the nutrient gelatine and produced conidia of 
Hormodendron. The production of conidia of Hormodendron was not 
