232 INJURIOUS AND USEFUL INSECTS 



is sometimes called the Campodea-larva, because it nearly 

 resembles Campodea and other adult insects of the lowest 

 grade, which undergo no metamorphosis, and are probably 

 the most primitive of still-surviving insects. This larva 

 occurs in the ametabolic orders, as well as in Coleoptera 

 and Neuroptera. 



The two following larvse are special modifications of the 

 long-legged larva. 



The Lamellicorn or Chafer-larva (Coleoptera). This is 

 the long-legged larva, altered by an inactive, subterranean 

 life. The abdomen is large and soft, especially behind, and 

 bears no appendages. There are three short thoracic legs. 



A footless larva, which differs from a maggot in having a 

 well-developed head, with biting mouth-parts. It may be 

 derived from the chafer-larva, or direct from the long-legged 

 larva, and is characteristic of insects in which the larva is 

 not compelled to travel in search of food. The best examples 

 are found in Coleoptera (longicorns, weevils), and in those 

 Hymenoptera which lay up food for their young, or are bred 

 in living insects. 



2. The Caterpillar. — The head is well developed, and bears 

 biting jaws and inconspicuous antennae. The body is soft, 

 and often cylindrical. Three pairs of short thoracic legs, 

 and a variable number of abdominal pseudopods, or false 

 feet, are usual. This larva occurs in Lepidoptera, Panorpae, 

 and some Hymenoptera (saw-flies). It is sometimes preceded 

 in the life-history by the long-legged larva, from which it is 

 evidently derived. 



The larvae of caddis-worms (Trichoptera) resemble cater- 

 pillars in some respects, but have at most one pair of 

 pseudopods, or false feet, on the last segment. They are 

 specially adapted to aquatic life, and dwell in movable 

 cases. Their origin cannot be traced, though they are no 

 doubt derived in some way or other from the long-legged 

 larva. The Nemoceran (Dipterous) larva has no jointed legs, 

 but pseudopods, or false feet, may occur on a few or several 

 segments. The head is either completely external and well 

 developed, or more or less retractile into the thorax, and 

 reduced. Some Nemoceran larva have no feet of any kind, 

 and only posterior spiracles. The maggot is the extreme 

 term of this series. 



