62 SOME INSECTS INJUKIOUS TO TRUCK CROPS. 



the larvae hatched December 4. These inohed between December 10 

 and 13, while being transported to Orlando, but soon died, as frost 

 killed otf the food plants. 



July 25, 1908, Mr. H. H. Dickson asked for a remedy to apply 

 against the larvae on sweet potatoes at the Orlando Truck Farm, 



Egg-masses received May 24, 1907, hatched at that time and the 

 larvae entered the earth in the rearing cage June 19. In dry sand the 

 pupae were found at a considerable depth, but in moist sand they 

 were found barely under the surface. 



July 8 larvae in the rearing-cage were almost full grown. Larvae 

 hatching from egg-masses, and others a few days old, were also 

 found in abundance on sweet-potato plants. As soon as hatched 

 they separate, feeding on the leaf on which the egg-mass was laid, 

 perforating the underside full of minute holes, and leaving only the 

 upper epidermis, which turns brown. On growing larger they sep- 

 arate, as in the case of most caterpillars, except those of peculiarly 

 gregarious habit, and soon become w^idely scattered. Even when 

 abundant it is common to see eight or a dozen on the underside of a 

 single leaf, and frequently as many as an hundred. Occasionally a 

 nearly full-grown larva feeds on the upper side of a leaf. In many 

 cases large larvae were found hiding during the day at the bottom of 

 furrows. 



June 15, 1908, the larva^ of this insect Avere found to be very abund- 

 ant at Orlando, Fla., in one part of the town feeding on pokeweed, 

 and in another on amaranth. 



EARLY RECORDS. 



Among the records of the Bureau of Entomology is one of May 22, 

 1887, when larvae and pupae were received from Mr. E. A. Schw^arz 

 Avith report that the species was very injurious to the eggplant at 

 Cocoanut Grove, Fla. 



In September, 1905, Mr. F. C. Pratt sent to the Bureau a large 

 colony of the larvae found feeding on pokeweed at Dallas, Tex., the 

 moths from wdiich began to issue September 26. 



LIFE-CYCLE PERIODS AND GENERATIONS. 



Larvae mailed from Orlando, Fla., July 3, arrived at Washington, 

 D. C, July 5 and began to enter the earth for pupation the following- 

 day. On the 16th two had transformed to pupa\ on the day folloAv- 

 ing three more, and the remainder transformed within a w^eek. This 

 experiment shows a pupal period of about 9 days, allowing 1 day for 

 the larvae in the earth before pupating. The weather was quite hot. 

 In a cooler temperature in August the pupal period required 11 to 

 13 days. 



The moths hatched from different lots were separated and the egg- 

 period observed. In one case this lasted from August 8 to 12, or 



