34 Timehri 



shells with a special organ known as the ovipositor. The eggs of the 

 parasites rapidly hatch into tiny grubs that eat up the egg -yolk in which 

 they find themselves immersed, and thus prevent the hatching of hurtful 

 caterpillars or larvae. The grubs, of which sometimes half-a-dozen or 

 more may obtain enough sustenance in a single egg, then change into 

 pupae, and finally into adult parasites, which then emerge into the outer 

 world by breaking a hole in the lepidopterous or other egg-shell which 

 imprisons them, and fly off to parasitize other eggs in turn. 



Not only are the eggs of Laphygma frugiperda parasitized, but the 

 caterpillars for these are attacked by an ichneumon named Enicospilus 

 fjuyanensis by Cameron. In its larval stage it feeds inside the caterpillars, 

 one to each caterpillar, and emerges as an adult from a tough brown cell 

 which is more rounded and more tapering at the posterior than at the 

 anterior end. It is one of our commonest ichneumons, and is sure to put 

 in an appearance in cane-fields whenever its host is in season. 



It may be mentioned here that the caterpillars of Laphygma frugi- 

 perda are cannibalistic, preying not only on one another but on cater- 

 pillars and pupae of skipper butterflies. If they happen to enter the 

 retreat of a skipper caterpillar they do not hesitate to attack any 

 caterpillar or pupa hidden therein. They are therefore both enemies 

 and friends of the planters, but on the whole they are more enemies than 

 friends. 



Galigo oberon, one of our biggest butterflies, is frequently met with 

 in cane-fields. A check on its undue multiplication occurs in the shape 

 of a Chalcid parasite, which emerges from the pupa of the butterfly. A 

 pupa which has suffered parasitism is readily recognisable by the holes 

 gnawed in it by the parasites at the time of their emergence. 



The caterpillars of about a dozen skipper butterflies (Hesperiidct) 

 may be found in our cane-fields. They form retreats by folding the 

 blades edge to edge, or by making one or more incisions from the edge 

 towards the midrib, and then folding over the portion next the one 

 incision or between the two incisions. These retreats although indicat- 

 ing to parasites the position of their host must be regarded as protective 

 on the whole. Hymenopterous parasites of skippers include a Joppa, a 

 Zelemorpha, and Chalcis annulata. The first and third emerge from 

 pupae of the butterflies, the second from caterpillars. 



The Joppa larva hollows the skipper pupa to a mere shell, and 

 itself transforms therein to a pupa, which is fairly discernible on account 

 of the semi-transparency of the pupa shell of its host. In due time the 

 head part of the skipper pupa is broken away and out comes the lively 

 parasite. But a single Joppa occurs in a pupa. 



Several individuals, however, of Chalcis annulata, a very common 

 insect, occur in a pupa, and on emerging leave ugly looking holes to tell 

 how the pupa met its death. Attacked pupae turn dusky yellow brown 

 with the skin glassy and transparent. 



