254 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



objective; while in Syritta pipiens they are hardly made out with less 

 than a 1-4 in. objective and are not as definite at any magnification. 

 Color white. 



Larva (Figs. 37-4, 5, 9). Superficially resembling the larva of T. 

 quadrata, especially in the differentiation of the anterior segments into 

 a false-head and in the possession of three pairs of lateral fleshy pro- 

 jections just anterior to the short, posterior respiratory process. It 

 differs from T. quadrata in its much smaller size, in being less nearly 

 cylindrical, broader m the median segments, and somewhat flatter; the- 

 posterior respiratory organ is relatively longer and slenderer and the 

 constriction between segments three and four (at the side of the false 

 head) more marked. 



Length about 10 mm., maximum width about 2.75 mm., maximum 

 height about 2 mm. Broadest in the region of segments seven to mine. 

 Tapering moderately backward to less than half the width at the 

 base of segment twelve ; much more moderately toward the head. 

 The false head 1.75 to 2 mm. broad, not as well developed as in 

 T. quadrata. Color dirty yellowish. The entire integument covered 

 with pale and delicate, close-set microscopic hairs, longer on the more 

 exposed portions. The false head lacks the conspicuous hooks or 

 thorns of T. quadrata, the vestiture being specialized only into the 

 transverse band of microscopic hooklets above the mouth. Antennae, 

 mouth-hood and lateral mouth-folds not differing noticeably from 7". 

 quadrata. The false-head with about a dozen longitudinal furrows, 

 one on the mid-dorsal line. The anterior larval spiracles located, 

 between the first and second furrow from the mid-dorsal line, sessile ; 

 each apparently with three rounded nodules on its summit. There 

 are seven pairs of prolegs on segments 3 and 5 to 10, inclusive, the 

 first pair situated more widely apart than the others, the last pair 

 smaller, each with about two dozen hooklets of varying size. 



The posterior respiratory organ is a brown, chitinized, polished tube, 

 projecting about .75 mm. (.5 to 1 mm.) its width ranging from .25 to 

 .35 mm., its depth from .2 to .25 mm. A little broader at base than at 

 apex, the latter truncated. The tube is semi-transparent and the two 

 large tracheal trunks can be seen throughout its length. The stigmal 

 plates similar to those of T. quadrata but with distinct differences. 

 The most important difference is that the three pairs of spiracles are 

 less distinctly S-shaped and each is ornamented with from nine to four- 

 teen (compared with about twenty for T. quadrata) of rounded lateral 

 projections or denticles irregular in size and irregularly distributed. 



Puparium (Fig. 37-6, 7, 8). Dimensions (15 specimens) : Length, 

 inclusive of the posterior respiratory appendage which retains the same 

 dimensions as in the larva, 5.9 to 7.9 mm., average 6.8 mm. ; maximum 

 width 2.75 to 3.4 mm., average 2.95 mm. ; maximum height 2.65 to 

 2.95 mm., average 2.68 mm. In outline elongate ovate, a little more 

 attenuated posteriorly, this attenuation more pronounced than in T. 

 quadrata. Nearly circular as seen from in front a little flattened on 

 the venter. The ventral line as seen from the side, straight from mouth- 



