INSECTS AND OTHER ANIMAL Pests INJURIOUS To FIELD BEANS 963 
missed in that year, owing to the delay in opening the laboratory. In 
that year the spring was very late and the rainfall was heavy thruout 
June and July. 
In 1918 a few females with well-developed eggs were found on May 9. 
It is not definitely known whether these flies hibernated as adults or 
were very early specimens of a main brood which came later. Judging 
from the number of flies taken in the field, the maximum emergence of 
first-brood flies occurred between May 23 and 26. Second-brood flies 
appeared in the cages from June 26 to July 5. After July 23 only one 
fly was found. This was a male, taken on August 26. In that year 
there were apparently only two broods. The adults came out early in 
the spring, but, as a result of the hot, dry weather at Perry in late July. 
ether the flies died or the development of the stages of the following 
brood was retarded. 
In 1919 a few flies were found after May 15, but it was not until June 2 
that they were at all abundant. They could stil be found easily on June 
9, and occasionally until June 17. Most of the females deposited their 
eggs during the first week of June. Second-brood flies appeared ‘n the 
cages from June 18 to July 3, with the maximum emergence about June 25. 
The hot weather of mid-July must have proved fatal to most of the flies, 
for they disappeared entirely and no more were seen until September 9. 
Then, for a few days, flies of the third brood were taken. In 1919 there 
were apparently three broods, or at any rate two and a partial third. The 
data leading to this conclusion are given in table 3: 
TABLE 3. Summary or Recorps TENDING TO SHOW THE NuMBER OF Broops In 1919 
Date Observations 
May 15 | 307, 69, taken by sweeping; 22 containing well-developed eggs 
20 | A few flies taken in an old wheat field 
27 | Flies still scarce 
29 | 27, 39, taken; eggs small; few flies seen; weather cold 
June 2 | Flies plentiful; eggs in females ranging from partly developed to mature 
4 | Eggs found on decaying material in cages; females in field containing a few mature 
eggs or no eggs 
9 | Fewer flies; abdomens empty 
Small maggots found in beans planted June 2 
11 | 39 taken containing no eggs; abdomens collapsed 
19 | First of second-brood flies emerged in cages 
20 | 13 second-brood 2 from field examined; eggs undeveloped 
25 | Many second-brood flies coming out 
July 3 | A few second-brood flies still coming out 
15 | Weather hot; few flies 
26 | No flies seen; flies in cages dead, probably owing to hot weather 
Sept. 13 | 1c’, 39, taken on ground plowed for wheat; eggs immature 
15 | 1o taken 
