694 Howard . — On Diplodia cacaoicola , /\ Henn. ; 
it was found that the mycelium had penetrated to the mucilage 
surrounding the seeds and had completely invaded the interior 
of the pod. Numerous pycnidia were observed under the 
epidermis near the point of infection. The control pod gave 
negative results. This experiment is of some interest as it 
throws light on the steps by which a saprophytic form may 
gradually become parasitic, ' and confirms previous observa- 
tions on the influence of a nutritious food-material in in- 
creasing the activity of a Fungus. 
(i d ) Next, a preliminary experiment was performed on two 
nearly ripe cacao-pods, in order to determine whether 
infection could be produced by spores without previously 
wounding the rind. A drop of sterile water containing 
spores was placed on the surface of the pod, and was 
covered by a small glass cell which was sealed on to the rind 
by means of budding wax. The cell was covered with 
a dark bandage to shield the spores from direct sunlight. 
Seven days afterwards the spores had developed a mycelium 
on the pod, but penetration of the intact rind by mycelium 
was not noted in either case. Unfortunately time did not 
permit of carrying out further experiments to settle this point 
definitely ; but a consideration of natural infections seems to 
indicate that pods at any rate are capable of being infected 
by germinating spores directly. If this were not the case 
it is difficult to explain why infection almost always begins 
at those points on the pod which are moist for the longest 
time, viz. the free end of the pod, the groove at the insertion 
of the stalk, and the place where pods come in contact with 
the branches. 
2. On the cacao trees : 
In the infection-experiments performed on the cacao tree 
itself, a small portion of the outer dry bark was carefully 
removed and the exposed bast washed with sterile water. 
A small chamber was made by raising the bark and cutting 
out a small portion of the bast down to the cambium. After 
introducing the infecting material, the bark-lid of this 
chamber was depressed and the whole covered with a water- 
