14 CEREAL AND FORAGE INSECTS. 



DESCRIPTIONS AND LIFE-HISTORY NOTES. 

 THE EGG (fig. 9, O) . 



A correct description of the egg can not be given, as all those ob- 

 served are from dissections and have not retained their normal shape. 

 They are a little over 1 millimeter in length and over one-half 

 millimeter thick, obtusely rounded at ends. The chorion is minutely 

 reticulate. In color they are a delicate white. It is probable that 

 they are deposited somewhere below the surface of the soil, as the 

 larvae are blind and are found quite deep in the earth. Nothing is 

 known relative to the period of incubation, as the eggs have never 

 been found in the fields. Numbers of adult females were dissected 

 and none contained more than three to four mature eggs, but they 

 could be found by this method from early spring on throughout the 

 entire summer. 



THE LARVA (fig. 9, b, e,f). 



Following is a detailed description of the larva: 



Color: Head and prothoracic plates dark brown, plates of the other two thoracic 

 segments much lighter; cerci and anal tube brown, somewhat dusky at the tips; 

 abdominal segments pale yellowish; tips of mandibles black; legs dusky. Just after 

 molting the larva is a delicate creamy white. 



Form: Depressed fusiform; breadth greatest at about the fourth abdominal segment; 

 length a little over six times the greatest breadth; thoracic segments narrower than the 

 abdominal ones. 



Head quadrate, depressed dorsally, with a deep, broad furrow starting at the base of 

 the antennae and extending in a posterior direction, gradually fading out; epistomal 

 sutures joining near the base of the head; a deep impression on each side of the head, 

 near the base, extending beneath and then anteriorly to base of mandibles; on the 

 dorsal surface there is a chitinous ridge at the base of the antennae. 



Ocelli absent. 



Epistoma reaching posteriorly about three-fourths of the distance from the front of 

 the clypeus to the occipital foramen, its lateral sutures sinuate; frontal angles obtuse, 

 rounded. 



Clypeus fused with the epistoma. Labrum bilobate, with deeply serrated margin. 



Setae: Dorsally there is one large and one small seta immediately at the base of the 

 mandibles; a large seta on each side near the margin of the epistomal area, posterior to 

 the antennae; several small setae on the clypeal and epistomal areas; a large seta and 

 several smaller ones near the center of the frontal angles; two large setae and several 

 small setae on the lateral margin of the head; one large seta near the base and slightly 

 ventral of the antenna; a small seta ventral of this last one; numerous medium-sized 

 setae on the ventral aspect. 



Antennae four-jointed; first two joints clavate-cylindrical, joint 2 four-fifths as long 

 as joint 1 and at the base about three-fourths as thick; joint 3 broadly clavate and 

 about one-third longer than joint 2, its outer angle truncate and bearing a prominent 

 acorn-shaped appendix; joint 4 slender, cylindrical, and slightly pointed at the ex- 

 tremity; joint 3 with two large setae toward the apex, one on the outer and one on the 

 inner margin, and one on the dorsal face near the base; joint 4 with three large and two 

 small setae at the distal extremity. 



