16 ON THE ORIGIN AND [CHAP. 



The order Strepsiptera are a small, but very re- 

 markable group of insects, parasitic on bees and wasps. 

 The larva (PI. IV., Fig. 8) is minute, six-legged, and 

 very active ; it passes through its transformations 

 within the body of the bee or wasp. The male and 

 female are very dissimilar. The males are minute, 

 very active, short-lived, and excitable, with one pair of 

 large membranous wings. The females (PL III., Fig. 

 8), on the contrary, are almost motionless, and shaped 

 very much like a bottle ; they never quit the body 

 of the bee, but only thrust out the top of the bottle 

 between the abdominal rings of the bee. 



In the order Coleoptera, the larvae differ very much 

 in form. The majority are elongated, active, hexapod, 

 and more or less depressed ; but those of the Weevils 

 (PL II., Fig. 6), of Scolytus (PL II., Fig. 4), &c., which 

 are vegetable feeders, and live surrounded by their 

 food, as, for instance, in grain, nuts, &c, are apod, 

 white, fleshy grubs, not unlike those of bees and ants. 

 The larvae of the Longicorns, which live inside trees, 

 are long, soft, and fleshy, with six short legs. The 

 Geodephaga, corresponding with the Linnaean genera 

 Cicindela and Carabus, have six-legged, slender, car- 

 nivorous larvae; those of Cicindela, which waylay 

 their prey, being less active than the hunting larvae of 

 the Carabidae. The Hydradephaga, or water-beetles 

 (Dyticidse and Gyrinidae), have long and nairow larvae 

 (PL IV., Fig. 6), with strong sickle-shaped jaws, short 

 antennae, four palpi, and six small eyes on each side 

 of the head ; they are very voracious. The larvae of 

 the Staphylinidae are by no means unlike the perfect 

 insect, and are found in similar situations ; their jaws 



