238 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



Mature larva: Length about 11 mm., width about 2.5 mm., height 

 about 2 mm. (Fig. 32-46). Compared with many other aphidophagous 

 larvae this species is noticeably elongate, slender, with more nearly 

 parallel sides. Segments 6 to 11 of nearly equal width, the twelfth 

 narrower and much depressed. Anterior to segment six the body tapers 

 evenly to the mouth-parts when extended, or rounds off at segment four 

 when at rest, with the head segments retracted. Body- wall prominently 

 wrinkled and with the usual two longitudinal carinas at each side. 

 General color yellowish, or salmon-brown, marked with black and 

 white. The whitish markings consist of a transverse, rectangular bar 

 on each segment, from six to eleven, and a narrow line along each 

 side of the larva in the dorsal lateral carina. Interrupted by the 

 transverse white bars at each segment, is the mid-dorsal heart-line, 

 consisting of six elongate, wedge-shaped, black marks, broadly mar- 

 gined with brown. Laterad of the brown are other prominent black 

 blotches extending obliquely outward and back to the whitish lateral 

 carinas. The anterior two or three segments unmarked with black or 

 brown; light greenish-yellow in color. The amount of brown color 

 variable, frequently covering the entire dorsum except the heart-line 

 in segments ten to twelve. 



The entire dorsum of the larva covered with short, close-set, black, 

 integumental spines. The segmental hairs larger but light in color and 

 not conspicuous, situated on slight elevations. 



The posterior breathing appendages on the dorsum of the last seg- 

 ment, (Fig. 32-46, c ; 49; and 50) are short (0.2 to 0.25 mm. long) and 

 nearly twice as broad (0.4 to 0.5 mm.) ; divergent for half their length; 

 the dorsal spiracular spines (Fig. 32-49 and 50, a) moderately long, 

 sharply conical, with a very small lateral sub-basal spur. The six 

 elongate spiracles (b) are irregularly and considerably curved, about 

 0.2 "to _ 0.25 mm. long, the median one on each side nearer to the ventral 

 than to the dorsal one. 



The anterior prothoracic spiracles on the third segment (Fig. 32- 

 46, b; 47, a) are small,, subcrescent shaped, the lip of the spiracle 

 marked by nine rounded, tooth-like lobes, (Fig. 32-48). 



The mouth-parts (Fig. 32-47, c, d, e) consist of the usual pair of 

 beak-like jaws (c, d) and three pairs of mouth-hooks (e). The jaws 

 are A-shaped, sharp, slightly hooked at the tip, somewhat shorter than 

 usual, the dorsal extending slightly beyond the ventral when apposed. 

 The latter has a ventrally projecting basal spur on each .side. The 

 mouth hooklets are unequal in size the outer pair largest ; the other 

 two pairs are situated close beside the jaws, the dorsal ones heavier, 

 the ventral pair small, slender. 



Puparium. (Fig. 32-57, 52, 53, 54, 55, 56). Dimensions, average of 

 15: Length 6.5 mm., height 2.5 mm., width 2.6 mm. The head seg- 

 ments of the larva are retracted ventrally so that segments 3 to 5 lie 

 at the anterior pole and the tip of the mouth-parts (terminal in the 

 larva) are about 0.5 mm., back on the ventral side. The wrinkling of 



