268 Maine Agricultural Experiment Station. 1917. 



changes, even in pupae which have come from the same egg 

 cluster, but the sequence of the changes and the pigmentations 

 themselves take place very constantly. 



The elytra do not become pigmented at all during the pupal 

 period, although the true wings become dark gray or almost 

 black ; since the wings lie under the elytra, the latter appear as 

 if they were colored gray, but if one lifts them up, it is clearly 

 seen that they are uncolored. 



Another point which should be noted is the fact that no 

 pigment is deposited in the pupal cuticula. The imaginal cuti- 

 cula begins to be formed on the 3rd or 4th day of pupal life, and 

 all of the pigment is formed in this cuticula. The pigmented 

 imaginal cuticula shows up very plainly inside of the sheaths of 

 pupal cuticula which enclose them. The imaginal mouth-parts 

 are not completely formed at the molt to the pupa, and the 

 pupal sheaths are much larger than the organs developed within 

 them. 



THE ADULT. 



Description. 



"Oblong, subparallel, above blue or slightly bronzed, usually mod- 

 erately shining, sometimes subopaque. Antennae^ half as long as the 

 body, piceous, joints 2-3-4 gradually increasing in length. Head feebly 

 shining, frontal carina obtuse, tubercles usually well marked, a few 

 punctures extending across the head above the tubercles and near the 

 eyes. Thorax one-half wider than long, slightly narrower in front, sides 

 feebly arcuate, the margin very narrow, disc moderately convex, the 

 ante-basal transverse depression rather deep, slightly sinuous at the 

 middle, reaching the sides and joining the marginal depression, surface 

 distinctly alutaceous, sparsely punctulate, punctures more distinct near 

 the apex and the front angles. Elytra distinctly wider at the base than 

 the thorax, humeri distinct, umbone moderately prominent and with a 

 slight depression within it, a prominent lateral plica begins at the umbone, 

 extends parallel with the margin, curves toward the suture near the apex, 

 surface alutaceous, the punctures fine and indistinct, not closely placed. 

 Body beneath and legs blue black, shining, abdomen sparsely and indis- 

 tinctly punctate. Length 20-24 inches ; 5-6 mm." 



The above description is copied directly from Horn (1889). 

 The Maine forms are usually bright cobalt blue, but rarely 

 they may be a greenish blue. The writer has never seen any 

 bronzy or subopaque forms in the state. The lateral plica varies 



^The italics are the writer's ; there are no italicized words in Horn's 

 description. 



