INSECTS. 121 



The celebrated Dead Sea apples, described by Sfcrabo, the 

 existence of which was denied by some authors, have recently 

 had their true nature ascertained. They are galls, not fruit, 

 of a dark reddish purple colour, and about the shape and size 

 of small figs. The inside is full of a snuff-coloured, spongy 

 substance, crumbling into dust when crushed; and this fur- 

 nishes the guides with an opportunity of playing " tricks upon 

 travellers." " The Arabs," says Mr. Elliott, " told us to bite 

 it, and laughed when they saw our mouths full of dry dust." * 

 Moore has very felicitously referred, in his Lalla JRooJch, to 

 those 



" Dead Sea fruits that tempt the eye^ 



But turn to ashes on the lips." 



In the next division (Ichneumonidce, Figs. 105, 107) we 

 find the insects depositing their eggs, not on the leaf or stem 

 of a tree, but actually in the body of a living caterpillar. 

 Because of their services in thus preventing the too great 

 multiplication of insects, Linnams gave to them the name 

 Ichneumon, thus indicating an analogy in their habits to those 

 formerly attributed to the quadruped of that name, as the 

 destroyer of the crocodile. About three thousand species of 

 Ichneumons are at present known and described. " They all 

 deposit in living insects, chiefly while in the larva state, 

 sometimes while pupae, and even while in the egg state, but 

 not, as far as is known, in perfect insects. The eggs thus 

 deposited soon hatch into grubs, which immediately attack 

 their victim, and in the end ensure its destruction. The 

 number of eggs committed to each individual varies according 

 to its size, and that of the grubs which are to spring from 

 them, being in most cases one only, but in others amounting 

 to some hundreds, "f 



In order to convey an idea of the services rendered by these 

 insects, Kirby and Spence inform us, " that out of thirty 

 individuals of the common cabbage caterpillar, which Reaumur 

 put in a glass to feed, twenty-five were fatally pierced by an 

 Ichneumon; and if we compare the myriads of caterpillars 

 that often attack our cabbages and brocoli with the small 

 number of butterflies of this species which usually appear, we 



* Trans. Entomological Society, vol. ii. page 14. 

 t Intr. to Entomology, vol. i. page 264. 



