40 DIPLODIA CORCHORI SYD. 
In Bihar, in 1918, the disease was generally much less than in the preceding 
year. This is probably to be attributed to the abnormal dryness (Plate VIII) of 
the air during September—October, when the disease is apt to spread most quickly. 
In all cases it was found that the late sown crop was relatively immune and the 
early sown, large, well grown crop was most liable to the disease. 
In Eastern Bengal, in August-September, 1918, the disease was present 
in Dacca, Mymensingh, Sinjhani and Haldibari. The number of diseased stems, 
however, was very small, and unless the disease appears earlier it is evidently not 
likely to be a serious source of damage to the fibre crop. An interesting fact 
observed was that in Dacca red-stemmed varieties of C. capsularis appeared to be 
much less susceptible to attack than green-stemmed, while C. olitorius appeared 
to be quite free from the disease. In Rajshahi the jute crop was C. olitorius and 
here also the disease was practically absent. 
In 1919 the condition of the jute crop on Dacca Farm by no means agreed 
with that in the previous season. The oliforius crop, both green and red-stemmed 
varieties, was attacked. The incidence of the disease was not heavy and varied 
considerably in different fields on the farm, the greatest damage seen in any one 
area, was probably about 10 percent. Red-stemmed C. capsularis was alsoattacked, 
These observations were quite sufficient to show that neither red-stemmed capsu- 
laris nor olitorius jute was resistant to the disease. At Chinsurah Farm the jute 
crop was C. olitorius, both red and green varieties being the same as at Dacca. The 
crop was in this case very fine, averaging about 14 feetin height, and there was nota 
single case of * black band’ disease. At Rangpur Farm both the olztorivs crop and 
green-stemmed capsularis were infected. The disease, however, only reaching an 
appreciable degree when the plants were of a certain size. 
In Bihar, in 1919, the state of the jute crop was very similar to that in 1918, 
A considerable portion of the seed crop had, however, been sown as late as June and 
this was invariably clean and healthy. In the more early sown areas the crop 
was only slightly diseased and not to an extent which would seriously diminish 
the yield. 
Reviewing these observations on the seed jute crop of the last three years 
certain general facts emerge :— 
(1) The disease exists in Bihar, Assam and Bengal, and is evidently 
well diffused over the whole jute-bearing area. 
(2) The incidence of the disease is in some way bound up with the crop 
reaching a certain degree of size. 
Beyond these facts, however, the evidences as to the conditions which favour 
the increase of the disease are confusing and will be considered later. 
