180 INSECTS. 



One of the best known of the Ichneumons is, per- 

 haps, the Yellow Ophion (PI. VI., fig. 4). Frequently 

 attracted hy the light through the open window in our 

 rooms on a summer evening, it seldom fails to attract 

 attention. Its active movements, its size (it is nearly 

 an inch in length), the beauty of its large, clear, bright 

 wings, and the noise which it makes in striking re- 

 peatedly against the ceiling, all render it difficult to 

 overlook the little visitor. Another genus of flies re- 

 sembling the Ophion is Paniscus, which may be dis- 

 tinguished from it by the presence of a very small 

 triangular cell (the " second S sub-marginal"), which is 

 wanting in the wing of the Ophion. The Ophion is 

 also to be distinguished by its beautiful comb-like foot- 

 claws. 



The Ophion differs from most of the IchneumonidaB 

 in depositing her eggs,not within the body of her victim, 

 but upon its surface. According to Kirby and Spence, 

 the egg is curiously attached to the body of the Cater- 

 pillar by a short footstalk, which is fastened into the 

 skin by an enlargement of the lower end, like the root 

 of a hair. The Ophion larva, when hatched, does not 

 quit the egg, but, keeping its hinder end within the 

 broken shell, and laying hold of the Caterpillar with 

 its jaws, remains feeding in this position till the time 

 for its change. So firmly fixed is it that not even the 

 moulting of the Caterpillar dislodges it. 



The greater part, however, of this family lay their 

 eggs within their victims, which are usually the larvse 

 of insects, sometimes the perfect insects and sometimes 

 the eggs. The benefit thus conferred by the Ichneu- 

 mons upon man is inestimable. They appear to be the 

 principal means employed to check the devastations of 



