42 



bloom on the surface. The hirva is of the normal tenthreclinid form, 

 the surface not very strongly wrinkled, G-annulate, smooth, and not 

 shining; the head is pale, nearly white, or pale green tinged with 

 brown, clypeus with a distinct brown spot, a brown band sometimes 

 jjresent above the clyj^eus, head usually darker on the upper third; 

 eyes black, mouth-parts dark brown, tips of mandibles darker; the 

 lateral surface, as Avell as the lower, varies from pale yellowish to 

 jjale but distinct green, this color extending from the line of the spir- 

 acles, the darker coloration of the dorsal surface often almost envelop- 

 ing the spiracles; body slightly brownish in the folds; spiracles 

 small, elongate-oval, black. Segment 13 is much paler dorsally than 

 the remaining segments. Besides the three pairs of nearly white 

 thoracic legs, which are more or less infuscated at the sutures, there 

 are eight pairs of abdominal legs (segments to 13), which are also 

 pale. Length, 13 mm. ; width, nearly uniform from the second 

 thoracic to the antepenultimate segment, 1.5 to 2 mm. 



Ayitepenidtirnate stage. — What appears to be the antepenultimate 

 stage closely resembles the mature form, but is less greenish in color 

 and has a proportionately larger head. In this stage, larvae are pale 

 green, wath a somewhat irregular, ill-defined, broad, darker green 

 space on the sides just above the spiracles; wdiite piliferous tubercles, 

 somewhat faint, but quite noticeable in living specimens, occur in this 

 stage. Length, 10 to 11 mm. ; width, 1.2 mm. 



Younger stage. — A still earlier stage was represented by very few 

 specimens and was very much darker. Dorsal surface pale brown, 

 shading into black at the sides; piliferous tubercles distinct, large 

 and white, arranged in regular sets; head almost uniformly dark 

 brown. Length, 7 to 10 mm. ; wddth, 0.9 to 1 mm. 



Larvae placed in a rearing cage in the insectary did not feed on 

 sugar-beet leaves, but when dock was substituted fed until maturity. 

 From these larvae three adults issued September 2-1. Larvae kept by 

 the junior author with him on his trip Avestward were confined in a 

 small tin box and fed on beet leaves. P^rom these one adult issued 

 October 3. The larva from Avhich this adult came formed a naked 

 jjupa in the box September 23, and this pupa was kept wrapped in a 

 beet leaf until the adult issued. 



The pujKi. — The pupa is at first pale green, with dark extremities 

 and tips of feet and palj^i brownish. Before the adult emerges the 

 pupa darkens considerably. Length, 10 mm. 



The adult. — The general appearance of the adult sawfly and the 

 arrangement of the venation of the wings is shown by figure 15, a. 

 A brief characterization of the genus was given by Norton in 1868," 



"Trans. Amer. Ent. Soc, Vol. II, p. 211. 



