99 THE JOLA OR DECCAN GRASSHOPPER 
main roads where the trafficis heavy. A similar localized 
distribution occurs in Bellary District and the same is the 
case with regard to those portions of Dharwar District 
bordering on Mysore. The reason for this localization 
is not clear but a possible explanation is given below. 
The fact that this pest has been doing damage for 
only a comparatively short time prevents us from expect- 
ing that this localization will persist. In fact, we may, 
with a fair degree of certainty, predict that the insect will 
spread from these various centres, so that in compara- 
tively few years it will cover those taluks already infested 
and will gradually spread out from them to the neighbour- 
ing ones, so that the whole of the northern part of the 
State where dry land cereals are extensively grown is in 
danger of infestation within a comparatively short time. 
CAUSES FOR UNEQUAL DISTRIBUTION OF THE 
GRASSHOPPERS. 
An examination of the map marking the distribution 
of the Jola Grasshopper in Mysore reveals, as already stated, 
the fact that this pest is not present over one continuous 
area but that it is to be found in more or less isolated tracts 
varying from one to several thousand acres. These tracts 
are, at times, considerable distances apart, so the question 
at once arises how the pest has spread from one to the other. 
That the pest has been present feeding on wild plants in all 
the localities now infested and that in all these centres it 
has gone over from wild plants to feed on cultivated crops, 
is highly improbable. The fact that the infested areas have 
been enlarging from year to year, in itself, indicates that 
this grasshopper, although wingless, has considerable 
powers of spreading. However, such a gradual spread can- 
not account for its appearance in distinctly separated tracts. 
The fact has, however, been observed in connection with 
the extensive cart traflic which takes place between places 
in Dharwar District and those in Shimoga or Chitaldrug 
District, that jola is usually cut and taken along as fodder in 
the carts." It might very well happen, then, that a cart 
eoing from an infested tract would take along with the 

1This fact was first brought to my attention, by B. C. Shantappa, Fieldman in my - 
office. 

