8 BULLETIN 967, U. S. DEPARTMENT OF AGRICULTURE. 



Egg. 



Length. 1.5 mm. ; width, 0.5 mm. ; shape almost cylindrical, but taperinj 

 slightly toward the posterior end ; color translucent yellowish white. 



Larva. 



Fig. 7. — Macrobasis im- 

 maculata: Triungulin. 



Triungulin (tig. 7). — Length, 2.7 mm.; width, 0.5 mm. through the head; 

 shape elongate triangular, tapering gradually to the posterior end, which is 

 bluntly rounded : color yellow or light brown, with lighter bands on the parts 

 of segments that fold against one another when the 

 body contracts in length ; legs 3-jointed, strong ; claws 

 three in number ( hence the name triungulin ) , slender, 

 the two outer ones spinelike ; eyes apparently only 

 pigmented spots behind the antenna? on the anterior 

 part of and near the outer margins of the head ; 

 mandibles flat, sickle-shaped, strong, with notched 

 inner margins ; antenme apparently 3-jointed, the third 

 joint divided with the dorsal portion the larger and 

 bearing several spinose hairs : spiracles 9 in number 

 and located above the lateral margins ; armature of 

 abdomen consisting of spinose hairs, about 10 in a 

 transverse row near the posterior margin of each 

 segment, and about 6 in a row nearer the anterior 

 margin, those in each row so placed as to be in rows 

 with corresponding hairs on the other abdominal seg- 

 ments ; anal segment with two diverging hairs one- 

 fourth to one-third length of body, projecting poste- 

 riorly from above its tip; hairs also regularly placed on thorax, head, and 

 upper and outer surfaces of mandibles: legs with stiff hairs projecting per- 

 pendicularly on the femur but appressed on the tibia. 



Carabidoid and scarabaeidoid larvw. — 

 Descriptions of these stages could not be 

 secured from authentic specimens, as they 

 were not reared. Collected larvae that 

 were thought to be in these stages were 

 similar to those figured by Riley 1 for 

 Epicauta vittata. 



Coarctate larva (fig. 8). — Length, 11.5 to 

 13.5 mm. ; width, 4.5 to 6.5 mm. ; shape 

 elongate hemispherical, resembling the half 

 of a peanut kernel if the ends of the latter 

 were bent toward its flat side and its edges 

 thickened ; color reddish brown ; entirely 

 inactive, the skin rigid ; location of ap- 

 pendages shown by tubercular projections; 

 limits of head shown by a constriction near 

 the anterior end ; segmentation of body 

 plainly shown dorsally but less distinct 



ventrally ; spiracles in shallow depressed line above the thickened edges. 



Third larva. — Measurements difficult to make, though greater than for the 



coarctate larva ; color white ; shape robust, fleshy, and much wrinkled, larva 





y 



a, 



CL 



Fig. 8. — llacrobasis immaculata, co- 

 arctate larva : a. Lateral view ; 

 a', ventral view. Enlarged. 



1 Riley, C. V., Packard, A. S., and Thomas, Cxrus. First Annual Report, U. S. Ent. 

 Comm., Dept. Interior, U. S. Geol. Survey, 1877, pi. IV, figs. 4-7. 1878. 



