74 



this date completed growth and entered the soil July 19, or in twenty- 

 one days. Eight days later pupation was completed and the two pupae 

 examined; appareDtly normal; removed to cage under cover for obser- 

 vation. One imago issued August 23, or twenty- seven days from 

 pupation. The other pupa was examined at this time and found to be 

 dead. 



Our records show these early larvae produce moths occasionally up 

 to September 5, but, so far as we are able to determine, the great bulk 

 of the pupae remain dormant until the following season. Of fed 

 larvae, the earliest record of issuance of the imago the following spring 

 in my notes is June 24. This larva completed feeding on August 4, 

 previous year, and went into the ground on that day. From this date 

 (June 24) up through July I have constant records of issuance of moths 

 from over- wintered pupae, the last date being July 29. Larvae occur, 

 feed, and pupate up to the last of September at Blacksburg, the last 

 ones usually occurring upon tomato. 



It would appear from my observations that this moth is, to a slight 

 extent, double-brooded at Blacksburg, but that on the contrary the 

 greater per cent of the overwintered pupae produce imagos in July, 

 and that the larvae from these moths quite invariably enter the pupa 

 state in twenty-eight to thirty days from hatching and lie dormant as 

 such over winter. 



The breeding experiments were carried on for two years and extended 

 into the third year. Many hundreds of larvae were under observation 

 during this time, but the procuring of accurate data was often much 

 interfered with by two enemies of this sphinx larva. 



These were the common Braconid Apanteles congregatus, the pupa 

 cases of which are seen so frequently attached to the larvae late in the 

 season, and a Tachinid fly of the genus Chaetolyga, the larvae of 

 which attack the horn- worm pupae in the soil. Many of our fed speci- 

 mens were in this wise destroyed, in some instances fully three-fourths 

 of the pupae being destroyed by the Tachinid. 



The discussion took the form of a number of questions propounded 

 to the author by Messrs. Johnson, Howard, Fernald, and others. 



HORNING SESSION, SATURDAY, AUGUST 20, 1898, 11.15 O'CLOCK. 



The first hour of the morning was spent by the association in the 

 joint meeting with the Society for the Promotion of Agricultural Science, 

 as already provided, listening to the reading of papers on entomological 

 subjects, the reports of which will be given in the proceedings of the 

 society mentioned. 



