12 STATE BOARD OF AGRICULTURE. 



Direct descendants from the Trichoptera are the Lepidoptera or 

 scale-winged insects including the butterflies and moths. Many of 

 the caterpillars of the lower forms of the moths still are aquatic and 

 live in cases, while many others that no longer live in the water yet 

 make cases, the common clothes moth larva being an easily secured 

 example. The Lepidoptera have the transformations complete, the 

 larvae, known as caterpillars, being vegetable feeders with few excep- 

 tions, while the adults, butterflies or moths are harmless, the man- 

 dibles becoming rudimentary and the maxilla formed into a long 

 coiled tube for sucking liquids. By this coiled tongue and the scaly 

 wings the Lepidoptera can be easily recognized at all times. 



The mud or earth living larvae developed at once into terrestrial 

 types and the oldest and most generalized of these are the Mecoptera 

 or scorpion flies. They derive their common name from the fact that 

 in the males many of them are furnished with a prominent anal 

 forceps curved upward like the tail of a scorpion, though it is entirely 

 harmless. The wings are long and rather narrow, net- veined and 

 not folded. They are peculiar in having the mouth parts prolonged 

 into a beak-like structure in which the parts are very much divided, 

 and their habits are predatory. 



There is no very obvious connection between the remaining orders 

 and any of the others, their descent from the Mecoptera type being 

 incapable of demonstration from living forms so far as known to me. 



The Hymenoptera contain the bees, wasps, ants, saw flies, ichneu- 

 mon flies and the like and, among them we find the very highest 

 types of social organization and the extreme of intellectual develop- 

 ment among insects. The mouth parts are in many cases elongated 

 to enable the insects to gather the nectar of flowers, and they have 

 four transparent wings with comparatively few veins. The trans- 

 formation is complete, and in many instances the larva is dependent 

 for its food upon the supply gathered by the parent. Most of them 

 are beneficial ; but there are some injurious groups, e. g., the 

 saw flies. 



The Diptera, or flies, can be always recognized by having two 

 wings only, the hinder pair having become rudimentary, serving at 

 present as poisers or balancers instead of organs of flight. Tbeir 

 larvae are mostly grub-like or maggots, and, while there is no develop- 

 ment of social or intellectual characters, the flies are in their trans- 

 formations and physical structure at the head of the insect world. 

 They contain both injurious and beneficial species, and their mouth 

 parts are adapted for either lapping, as in the common house fly, or 

 for piercing and sucking, as in the equally common mosquito. 



