684 Howard. — On Diplodia cacaoicola , P. Henn. ; 
diseases, and that ‘ root ’ disease is nothing more than a 
general term covering several apparently distinct maladies. 
During the early part of last year cultivation-experiments 
were performed with the Fungus, and no difficulty was ex- 
perienced in obtaining hanging-drop cultures containing a 
single spore. The germination of the spores was observed 
in several culture-media, and the Fungus was grown in flasks, 
in tubes, and on sterilized wood. At this time frequent 
absence from the laboratory and pressure of other duties 
prevented a complete study of the Fungus being made, and 
it was not till last December, when an outbreak of what was 
described as ‘ rind ’ Fungus occurred in Demerara and diseased 
canes were forwarded to the Department of Agriculture by 
G. S. Jenman, the Government botanist of British Guiana, 
that the study of this form was resumed. 
It was then found that the predominant Fungus on these 
canes was identical with the pycnidial form noted earlier in 
Barbadoes, and since many of the canes appeared to contain 
this Fungus alone, experiments which are described below 
were undertaken to follow the development of this form 
under artificial conditions, and to prepare pure cultures. 
About this time the cacao planters in Grenada had their 
attention directed to the diseases of cacao by the spread of 
‘ thrips,’ which did some slight damage to the pods and the 
young leaves of the trees. It was observed that several trees 
on which ‘ thrips * had been seen died off rather rapidly, and 
considerable alarm was caused by the belief that these insects 
might destroy the cacao industry in that island. An inves- 
tigation on the spot, however, showed that it was highly 
probable that the trees believed to be dying through the 
attack of the thrips were really being killed by Fungi, and 
that the insects were not more numerous on the diseased trees 
than on others which were quite healthy. Portions of the 
branches of such trees were collected and sent to Barbadoes 
for examination, when it was found that in all cases they 
contained the same Fungus, and that this was apparently 
identical with that found on the diseased sugar-canes from 
