282 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



that represent still earlier stages and the smallest an individual 

 but three and one-half millimeters long is probably the first, 

 while a larger one, four and one-half millimeters long, may rep- 

 resent the second instar. These complete a fairly regular series 

 from which we may present a brief statement of distinctive 

 characters. 



Description of Early Stages. 



First instar. Smallest individual seen, length 3.5 mm. Body 

 slender, abdomen scarcely wider than thorax. Head and thorax 

 with antennae and legs and the last segment of the abdomen 

 black polished. Abdomen except last segment yellow. An- 

 tensas short, first joint thicker, about as long as thick, second 

 scarcely longer than first, enlarging to tip, third short and with 

 the following joints forming an obscurely segmented terminal 

 part, tapering slightly to a blunt tip. 



The second instar as indicated by size and maturity is 4.25 

 mm. long with the color as in the first instar, but with a very 

 slight indication of beginning of the wing pads of the meso- 

 thorax. 



The third instar 5 mm. long has the coloration of the preced- 

 ing stage, but there is a distinct enlargement of the mesothorax 

 into developing wing pads, but scarcely any for the metathorax. 



Fourth instar. Length 6 mm. Head strongly produced semi- 

 circular from the base of the antennae. A transverse suture 

 across head, touching bases of antennae. Mesothoracic wing 

 pads extending back and enclosing metathorax and nearly 

 touching base of abdomen, metathorax strongly concave behind 

 the wing pads, not specially developed. 



Color : Head and thorax including wing pads fuscous or 

 nearly black, shining. Segments of the abdomen except the 

 terminal one yellow-white, terminal segment black, tubular, 

 legs black, tips of femora paler. Beneath ; front black, lower 

 part of face, legs and central stripe of abdomen brown, sides of 

 abdomen, segments 1 to 5 orange red. (See fig. 41 d.) 



Final instar. Length 11 mm., width 4 mm. Yellowish white 

 with brown spots, brown eyes, ocelli in brown spots. A pair 

 of spots on the prothorax, median and lateral spot on scutellum, 

 part ®f mesothorax, the border and a pair of spots near center 

 and the hind borders of the wing pads dusky ; terminal seg- 



