Larch Disease. 
171 
and the dead and dying trees on which an abundant growth of 
Dasyscypha was present, should be removed and burnt. Some 
small Douglas firs had beep planted amongst the larches, 
which were injured by Botrytis Douglasii v. Tub., a fungus 
that attacks the base of the leaf, which, being protected by 
scales, is soft. This disease was observed in 1904 on cedar, and 
described in the Report for last year. 
Specimens of young spruces from Northamptonshire showed 
the leading shoot broken off or doubled over. The trees were 
described as ten to twenty feet high, and the strongest and 
healthiest were injured. The member sending the specimens 
feared that it was due to an attack of the spruce bug, but no 
trace of this insect was present. It was clear that some fungus 
had caused the injury, and a further supply of specimens 
showed that it was a species of Cceonia , allied to C. pinitorquum 
Hart., a fungus which possesses the peculiar property of twisting 
the leading shoots of the Scotch fir. It is called in Germany 
by the characteristic name of twist rust. The fungus is usually 
more severe in wet years, but in dry years the mycelium 
spreads but little in the tissues. Vigorous trees get over the 
injury before any serious harm is done to the tree for use as 
timber. 
Several injuries to plants grown in greenhouses have been 
examined during the year. Such plants are more liable to 
be attacked by fungi than similar plants grown in the open 
air. Thus the fungus, Corynespora Mazei Giissow, described 
last year from cucumbers grown under glass, has this year 
been received from various localities over England, showing 
extensive damage done by it. The attacks of Corynespora , 
Cladosporium , Botrytis , and Alternaria are only dangerous 
when they attack the cucumbers in the greenhouse where the 
moist and warm atmosphere supply the conditions favouring 
the germination of the spores of the fungi, and the more 
delicate tissues of the host plant enable them more easily to 
enter it. 
A disease of tomatoes was investigated this year from 
specimens sent in the first instance from Jersey, and afterwards 
from Northampton. In Jersey it was causing great damage. 
The young fruits of the tomato begin to discolour, generally 
on the top, showing black or brownish depressions of various 
sizes, which increase outwardly in a circular manner. Small 
chains of bacteria have been obtained from the diseased 
tissues (see Fig. 2, D). Young and healthy fruits inoculated 
with the bacteria by Prillieux became diseased. At first it 
seems that these organisms obtain access to the fruit through 
the delicate tissues of the style, but they may take advantage 
of any little prick made by an insect in the skin. Earle 
