THE CANADIAN blNTOMOLOGiST. 23 



NOTES ON ZAR^EA AMERICANA.— CRESS. 



BY REV. THOMAS \V. FYLES, SOUTH QUEBEC. 



The young larva of Zaroea Americana appears in the beginning of 

 July on Meny ant lies trifoliata. It lies curled on the underside of the 

 leaf. Its head is black, and its body lead-colour above and greenish- 

 white beneath. It develops into the most beautiful larva of any of the 

 Tenthredinidae that I am acquainted with. 



Description of the full-grown larva. — Length one and a-quarter 

 inches. Head black. Body above lead colour — excepting the anal seg- 

 ment, which is greenish white. The underside and the legs are greenish- 

 white. The forelegs are tipped with black. Along the back are eleven 

 pairs of raised and conspicuous bright yellow spots. Between the pairs, 

 and on either side of them, are conspicuous jet-black spots, which, taken 

 with the yellow ones, form rows across the back. There are other rows 

 of smaller black and pale-yellow spots — two after each row of the larger 

 ones. The side lines are white. Above these lines, on the margin of 

 the lead-colour, is a row of black dots. Beneath them, just above the 

 legs, is a series of raised yellow spots — each spot being surmounted by 

 one or two black dots. 



The larvae were plentiful in one spot, but could hardly be said 

 to be gregarious, as only one or two were to be found on a plant. 

 Towards the end of July the larva spins around itself a closely woven, 

 dark-brown cocoon. In the spinning it usually gathers several leaves of 

 the plant about it. The larva remains unchanged in the cocoon till 

 spring, when it assumes the pupal state. The fly makes its appearance 

 in the middle of May. 



Description of the perfect insect. — In length the fly measures about 

 nine-twentieths of an inch ; and in expanse of wings about eighteen" 

 twentieths. The antennae are dark brown, six-jointed and clavated. 

 TJie wings are faintly clouded with brown. The head and thorax are 

 dark brown and hairy. The abdomen, which is oval in outline, is of a 

 rich velvety-brown above, with a slightly bronzy-green lustre. The 

 colour fades into light reddish-brown on the sides and on the two last 

 segments. The underside of the abdomen is pale brown. The tibiae 

 and tarsi are white, and have a waxen appearance. The fly seems to be 

 somewhat sluggish in its habits. 



I am indebted to Mr. E. T. Cresson for the identification of the 

 insect. 



