64 



of securing specimens and parasites, of very doubtful value from an 

 economic standpoint or as indicating- its normal habits. The observa- 

 tions have many of them been once and often twice substantiated. 



In ordinary seasons and throughout the area above indicated the 

 statement made long ago by Dr. Fitch that the Hessian Fly is double 

 brooded is true. While in the southern portion of the State the fall 

 brood of adults seem to appear some weeks later than in the northern 

 part, nevertheless I have found but two destructive broods. Between 

 these two broods, however, is a considerable mass of fluctuating indi- 

 viduals, the true position of which is rather anomalous.* 



At LaFayette, Ind., latitude 40° 27', wheat plants were transferred 

 from the fields to the breeding cages April 5, 1890, and kept out of 

 doors. The seed producing these plants had been sown the preceding 

 September 3. On April 17 a female emerged, and a male appearing 

 soon after, these, on April 22, were both placed together on young 

 growing wheat planted iu a breeding cage, out of doors. From these 

 adults were secured June 8. The attempt was made to follow the off- 

 spring of these, but failed on account of the wheat beiug killed by rust. 

 On June 7, and also on the 14th, 1888, in the same locality, adults were 

 observed ovipositing, the eggs being placed on the youngest and most 

 tender shoots, and there was every evidence that these eggs developed 

 through the larval to the flaxseed stage by early July. Besides, I have 

 observed in the same locality late-growing shoots literally overrun 

 with very young larvaB on the 26th of June, and found larvae as late as 

 the 10th of July. 



On October 16, 1887, Mr. W. S. Eatliff, who made a great number of 

 experiments for me, near Richmond, Ind. (latitude 30° 51'), secured 

 adults from a small plot of wheat plants which appeared above the 

 ground September 4. From a plant from this same plat that had been 

 transplanted indoors, he secured an adult female 11 days earlier. In 

 either of these cases with favorable weather the female could have 

 sent her offspring into the winter in the flaxseed state. Mr. Eatliff also 

 observed adults on July 10, 1887. At La Fayette, Ind., the same au- 

 tumn, I saw females ovipositing on November 3, in a temperature of 64° 

 F., among the plants. From a plat sown August 13, and which came up 

 on the 17th, I obtained adults of both sexes on October 1, 44 days after 

 the plants appeared and 48 days after sowing. That larvse, even 

 though quite immature when winter begins, may survive till spring has 

 been demonstrated again and again, and was especially true of the 

 exceedingly mild winter of 1889-'90. In fact, by a series of sowings all 



* Dr. Fitch states that the eggs of the fall brood are deposited in the State of New 

 York early in September, and also that " the deposit is doubtless made later to the 

 south of us than it is here in New York. " (Seventh Report.) Mr. Edward Tilghman 

 observed oviposition in Queen Anne's County, Maryland, about latitude 39° to 39° 

 30', during the second week in October, and mentions it as of usual occurrence. (The 

 Cultivator, May, 1841.) 



