50 
Elementary Manual of Zoology. 
sticky during two or three months, and they effectually prevent the caterpillar 
from ascending the tree. Secondly, all underwood was cut and burnt as far as it 
could vot be utilised. Poles fit for sale were barked and the bark was burnt with 
the rest. For this purpose special fire places were prepared and surrounded by a 
circular ditch with steep sides, to prevent the spread of the fire and the escape of 
the caterpillars, which, as soon as the underwood was heaped up inside the ditch, 
rapidly collected in the ditch and were destroyed. The moths commenced to swarm 
in this district, while huge masses of caterpillars were still at work feeding. Hence 
the fires lit to burn the underwood were also used to attract and destroy the moths ; 
for this purpose the fires were lighted at nightfall and kept up until midnight. 
Between nine o’clock and midnight the largest swarms of the moths appeared. A 
portion were actually burnt, the others were stupefied by the heat, fell to the 
ground, and were easily killed. Pine torches were also used with large screens 
behind them, smeared over with glue, on which the moths were caught. 
Thirdly, extraordinary efforts were made to destroy as many caterpillars 
and moths as possible. Gangs of women with blunt brooms and long handles 
were busy in the protection belt and elsewhere in the forest, in killing the cater- 
pillars, which were set in motion by the cutting of the underwood and other 
operations undertaken. For the destruction of the moths 300 labourers and 80 
boys under their masters were employed. This work could, as a rule, only be 
done early in the morning from four to half-past eight o’clock. Later in the day 
the moths fly about and cannot be caught. Only on cool rainy days do the 
moths remain quiet during the day and can be destroyed. 
“To return to the protection belts, the great object aimed at was to stop the 
spread of the caterpillars by making it impossible for them to ascend large trees, 
and by destroying the food which the underwood had furnished them. Here 
and there the success was not complete, and in such cases an additional protec- 
tion belt was formed outside the one first established. Upon the whole, the 
result was most satisfactory, and the destruction was confined to less than a 
sixth part of the entire forest. In some cases ditches with steep sides were used 
in addition to the protecting belts, and the caterpillars collected in them in large 
masses.” 
It should also be noticed that all leaf-feeding caterpillars can be 
destroyed by spraying the trees with arsenical insecticides, This form 
of treatment is being largely adopted for fruit trees in America and 
Europe, It is only likely to be of use in tbe case of specially 
valuable fruit trees in India. 
The School Museum contains numerous specimens in various 
stages of development for the students to examine. 
Psychide group (Bag-worms).—These insects defoliate plants of many 
kinds in India and do some damage in forests. The caterpillars 
may be recognised by the curious little cases composed of stick or leaf 
which they carry about upon their backs. The male is an obscure 
little moth, which is so active in its habits and lives such a short time 
that it is seldom noticed. The female is a degraded, wingless creature, 
which pever quits the case that is formed by the caterpillar. When 
the caterpillar is full fed it attaches the case by asilken strand to a 
leaf or twig. It then fastens up the open end with silk and trans- 
forms into a chrysalis. The female is fertilised by the male and lays 
