1220 



FAMILY LIU. CHRYSOMELID^. 



2257 (6995). 



<1. Surface shining:, the punctuation never very coarse; elytra each 



with a paler median stripe. 2260. T^NIATA. 



ild. Surface subopaque, the punctuation coarsp, close and deep; elytra 



without a paler median stripe. 2261. MARGTNAT.TS. 



SYSTENA IITDSONIAS Forst., Nov. Sp. Ins., 1771, 26. 



Elongate, subdepressed. Pic- 

 eous black, shining; antennae with 

 joints 3, 4 and 5 dull yellow, the 

 others more or loss piceous ; legs 

 black. Thorax about one-third 

 wider than long, sides feebly 

 curved, front angles obliquely 

 truncate; surface finely aluta- 

 ceous, indistinctly punctate, mi- 

 nutely wrinkled. Elytra wider at 

 base than thorax; disk coarsely and 

 closely punctate, somewhat rugose. 

 Length 4-4.5 mm. (Fig. 541.) 



Throughout the State; 

 frequent in the southern, 

 scarce in the northern coun- 

 ties. May 21- August 20. Oc- 

 curs on the greater ragweed, 



Fig. 541. X 10. (After Forbes.) 



Ambrosia trifida L. ; also on elder and other weeds. 



*225S (6996). SYSTENA FRONTALIS Fabr., Syst. Eleut, I, 1801, 300. 



Resembles hudsonius very 

 closely. Usually a little 

 broader and less shining, the 

 head reddish or reddish-yel- 

 low; antenna' and legs mostly 

 pale. Thorax more distinctly 

 and elytra less coarsely punc- 

 tate. Males in both species 

 with the last ventral segment 

 notched each side, the middle 

 lobe with a deeply impressed 

 triangular median line. Length 

 3.5-4.5 mm. (Fig. 542.) 



Throughout the State; 

 less common than liudso- 

 iiinx. Hibernates beneath 

 bark of soft maple and 

 mullein leaves. February 

 14-September 22. Occurs 

 most frequently on smart- 

 weed (Polygon um}, the 

 greater ragweed and pigweed (Chenopodium).. 



Fig. 542. ; 10. (After Forbes.) 



