LEPIDOPTERA 



215 



The Typical Pyralids 



There are only about twenty-four species in this group and the two 

 following are the best known. 



The meal snout-moth, Pyralis farinalis. — The larva of this species 

 feeds on meal, flour, stored grain, and old clover hay. It makes little 

 tubes composed partly of silk and partly of the fragments of its food. 

 It rarely occurs in sufficient numbers to do serious injury; and its 

 ravages can be checked by a thorough cleaning of the infested places, 

 or when practicable by the use of carbon bisulphide. The moth is com- 

 monly found near the food of the larva, but is often seen on ceilings of 

 rooms sitting with its tail curved over its back. It expands about 1 inch; 

 the fore wings are light-brown, crossed by two curved white lines, and 

 with a dark chocolate-brown spot on the base and tip of each. 



The clover-hay worm, Hypsopygia costdlis. — The larva of this species 

 sometimes abounds in old stacks of clover hay, and especially near the 

 bottom of such stacks. As the infested hay becomes 

 covered with a silken web spun by the larva, and by 

 its gunpowder-like excrement, much more is spoiled than 

 is eaten by the insect. Such hay is useless and should be 

 burned, in order to destroy the insects. The moth ex- 

 pands about f of an inch. It is a beautiful lilac color, 

 with golden bands and fringes (Fig. 370). 



Fig. 370. — Hyp- 

 sopygia costalis. 



The Close-wings or Crambids 



This is not a large group but the members of it are more often seen than 

 any other pyralids. The larvae of most of the species feed on grass ; and the 

 adults fly up before us whenever we walk through meadows or pastures. 

 When at rest, the moths wrap their wings closely about the 

 body ; this has suggested the name close-wings for the insects 

 of this group. When one of these moths alights on a stalk of 

 grass it quickly places its body parallel with the stalk, which 

 renders it less conspicuous (Fig. 371). Many of the species 

 are silvery-white or are marked with stripes of that color. 

 About seventy of our species belong to the genus 

 Crambus. The moths of this genus are often seen; but the 

 larva? usually escape observation. They occur chiefly at or 

 a little below the surface of the ground, where they live in 

 tubular nests, constructed of bits of earth or vegetable mat- 

 ter fastened together with silk. Thus Crambus caliginosellus 

 is known as the corn-root webworm on account of its injury 

 to young corn plants which it bores into and destroys; it 

 is also known as the tobacco stalk-worm, on account of 

 similar injury to young tobacco plants. 



Another species, Crambus hortuellus, is known as the 



cranberry girdler. It does considerable injury to cranberry 



vines by destroying the bark of the prostrate stems. 



To this subfamily belong the larger corn-stalk borer, Diatrasa zeacolelta, 



which sometimes bores into the stalks of young corn in the Southern 



States, and the sugar-cane borer, Diatraa saccharalis, which bores into 



the stalks of sugar-cane. 



Fig. 37I- — 

 Crambus. 



