144 



PESTS OF LEGUMINOUS CROPS. 



thrown out producing a somewhat stunted bushy plant. In all the cases 

 observed a very large percentage of the larvae are killed by parasites, 

 which puts a great check on the pest. The small white cocoons of the 

 parasite are found in the twisted leaves of the caterpillai-'s dwelling and 

 may be mistaken for some stage of the pest's life. The pupa of the pest 

 is the usual small brown pupa lying naked in the leaves. 



The pest has been found in several widely scattered districts in the 

 plains. It is most abundant in plots of unmixed tur, less so where tur is 

 sown with maize, til or other crops. These crops coming up more 

 rapidly than the tur, serve to hide it to some extent, and though mixed 

 crops are attacked, unmixed tur suffers more. Possibly this has some 

 connection also with the habits of the parasite which may prefer the tur 

 grown under shelter of another plant to tur grown in the open, and so 

 destroy the insect more largely. 



The very simple remedy of pulling off the affected leaves is suffi- 

 cient to check it. These knots of leaves are readily seen and can be rapidly 

 and easily collected by hand. The caterpillars collected should not be 

 destroyed but placed in a box or some closed receptacle ; 

 the parasites will hatch out gradually, and if the box be 

 cautiously opened in the day-time in bright light, they 

 will fly out ; the moths will not escape at the same 

 time if the box is carefully opened. In this way, the 

 valuable parasitic flies will not be destroyed, but will 

 return to the fields to complete their useful work. 



The Gram Caterpillar. 



The seeds of the gram plant are commonly eaten 

 by a large green caterpillar, somewhat over one inch 

 long when full grown, which sits on the outside of the 

 pod. This is a cosmopolitan pest ^ which attacks an 

 enormous variety of crops all over the world. 



The life history is identical with that of similar 

 caterpillars ; the eggs are laid singly on the food-plants, 

 small whitish eggs, round and beautifully sculptured ; 

 the caterpillars feed for a short time on the leaf or 

 the outside of the gram pod and then bite through to 

 the seeds ; they feed from outside, attacking one seed 

 after another, but not bodily entering the pod and 

 remaining there. This period lasts about a fortnight as 



Fig. 161. 

 Gram Caterpillar. 

 {Twice magnified.) 



PP, Chloridea olsoUta^ F. (Noctuidae.) The Aipericiin BpU-worjfl. 



