20 



ridges do not unite posteriorly, but are connected by a median, 

 crescent-shaped thickening. The operculum is nearly semi-circular, 

 reaching to about one-half the distance from the base to the apex of 

 the orifice, and the lingula has its side and terminal lobes more dis- 

 tinctly marked than before. The number of longitudinal rows of 

 minute setae on the upper surface of the lingula is now about 

 eighteen. A shallow groove extends from the apex of the orifice to 

 the caudal margin of the body. The antennae arise nearer the base 

 of the fore legs than in the previous instars, and may be partly con- 

 cealed by them. They are indistinctly segmented, thick at the base, 

 tapering toward the tip. The basal two-thirds of each is directed 

 inward toward the antenna of the opposite side, while the apical 

 third is bent backward toward the base, the whole forming a figure 

 not unlike the letter C. The first two pairs of spiracles now appear 

 as single slits, while the other two pairs are indistinct. 



The length of the body in this instar varies from .493 to .583 

 mm., the width from .275 to .352 mm. 



Pupa. (Plate III, Figs. 13 and 14; Plate IV, Figs. 15 and 16; 



Plate VI, Figs. 2S-31. 



The form of the pupa varies from irregularly oval to elliptical, 

 the broadest part- of the body being usually about two-thirds of the 

 distance from the cephalic to the caudal margin. When freshly 

 moulted the body is flat and thin, with no wax secretion, but as the 

 insect grows it becomes raised from the surface of the leaf by a ver- 

 tical wax fringe, the height of the body becoming about one-third of 

 its width. The dorsum is rugose, less noticeably so along the mid- 

 dle ; somewhat convex. There are three pairs of marginal spines as 

 in the two preceding instars. The first pair on the cephalic margin 

 are minute, as in the two previous instars, and frequently appear to 

 be lacking ; the caudal pair, arising a little inside the margin, are 

 less than one-tenth the length of the body, and the spines on the 

 caudo-lateral margin are less than one-half as long as the last men- 

 tioned. The caudal pair curve upward and backward, diverging at 

 the base, usually converging posteriorly. There are three pairs of 

 dorsal spines, as in previous instars. The first two pairs are minute 

 — the first pair being somewhat longer than the second. The third 

 pair is usually well developed, varying greatly in length in different 



