720 



REPORT UNITED STATES GEOLOGICAL SURVEY. 



brooded. " The young worm liatcLes about tlie 1st of July aud imme- 

 diately commences its work of destruction. It works in such a surrep- 

 titious manner as to be too often unnoticed till the vine is destroyed. 

 The plant does not generally show any signs of decay until the cocoon 

 is about fully grown, when it wilts and is past recovery. This occurs 

 about a jnonth after the worm is hatched, and it then crawls just under 

 the surface of the ground, fastens a little earth together around itself 

 by a slight net, and changes to a chrysalis of a very light mahogany- 

 brown color, and three-fourths of an inch long. The moth comes forth 

 the fore part of September. The careful culturist need fear nothing 

 from this troublesome insect, as an occasional close inspection of the 

 plants about the 1st of July will reveal the hole where the borer has 

 entered, which is generally quite a distance from the ground, and by 

 splitting downward one side of the stalk with a penknife it may be found 

 and killed. If this inspection be made at the proper time the worm will 

 be found but a short distance from the hole, and the split in the stalk 

 will heal by being kept closed with a piece of thread." — (liiley.) 



Descriplion of the Jarva. — Of a livid hue when young, with light stripes along the 

 body ; when iuU grown, it generally becomes lighter, with the longitudinal lines 

 broader. 



Moth. — Of a mouse-gray color, with the fore-wings finely sprinkled with Naples- yel- 

 low, and having a very faint lilac-colored hue ; but distinguished mainly by au arcu- 

 ated pale line running across their outer third. — (Riley.) 



Besides the chinch-bug, and also other insects already noticed among 

 those preying on wheat, the leaves of corn are infested by the young of 

 the large lo moth and by the Arctia arge. 



The cotton-boll worm {Heliothis annigera) sometimes attacks corn iu 

 the ear, eating the silk, and afterward devouring the terminal kernels, 

 hiding within the husk. Whole fields of corn have been thus injured 

 in Kentucky, but it is most destructive in Southern Illinois, where there 

 are two broods of the worm, the early and late corn faring the worst. 



INJURING THE ROOTS AND LEAVES OF GRASS. 



Besides most of the insects previously mentioned, which injure tbo 



roots and stalks of cereals, the 

 grass on lawns is often kdled 

 in patches by the white grub or 

 larva of the June beetle {Lach- 

 nosterna fusca, Fig. 10). So 

 effectually are the roots eaten 

 that the sod can be rolled up 

 like a carpet. The white grub 

 is injurious on lawns in Illinois, 

 as well as in the New England 

 States, Wire-worms, the larva 

 of the various species of Ne- 

 onympha, cut-worms, the larvte 

 of crane-flies ( Tipula),fiud of the 

 salt-marsh caterpillars ( Leu- 

 carctia acrcva), and very hom- 

 opterous insects, such as the 

 Fig. 10.— June beetle, Irtc/inosto-na/i(sca. I, larva; spittle insects, especially PtiJ- 

 2, pupa; 3, 4, adult. chd lineatiis, (Fig. 11), are de- 



pendent for their livelihood on grasses. TTie latter is a very abun- 



