734 
Journal of Agricultural Research 
Vol. XXI, No. IO 
No. io, i t?, i } P. regina; No. n, none; No. 12, i 9 M. domesiica; 
No. 13, none. June 2, 2.30 p. 111., No. 1, 1 9 P. regina , 1 9 C. macel- 
laria; No. 2, 5 9 P • regina , 1 $ C. macellaria (sex ?), 2 9 M. domesiica ; 
No. 3, 2 9 P- regina, 1 9 M. domesiica; No. 4, 2 9 P- regina; No. 5, 
none. June 3, 9.30 to 11.20 a. m., No. 5, none; No. 6, 1 9 M. domesiica; 
No. 7, 2 9 P • regina; No. 8, 9, and 10, none; No. 11, 1 9 C. macellaria; 
No. 12, 1 9 P. regina; No. 13, none. June 3, 1.30 p. in., No. 1, none; 
No. 2, 1 9 C. macellaria; No. 3, 1 9 P> regina; No. 4, 1 9 C. macel¬ 
laria. June 5, 10 a. m., No. 1 and 2, none; No. 3, 1 9 P • regina; No. 
4, 3 d P. regina; No. 5, 1 9 P- regina; No. 6 and 7, none; No. 8, 1 9 
C. macellaria; No. 9 to 14, inclusive, none. 
The grand total of all the colored flies caught in the traps was 126, 
distributed among the traps as follows: 
No. 1, 26 (P. regina 2 c?, 17 9 J C. macellaria 2 9 ; A/, domesiica 5 9 )- 
No. 2,21 (P. regina 16 9 ; C. macellaria 1 9 > 1 ?; M. domesiica 3 9 )• 
No. 3, 19 (P. regina 1 $, 9 9 I C. macellaria 3 9 ; M. domesiica 6 9 )• 
No. 4, 19 (P. regina 2 c?, 14 9 ; C. macellaria 3 9 )• 
No. 5, 15 (P. regina 11 9 I C. macellaria 3 9 > 1 ?). 
No. 6, 2 9 M. domesiica. 
No. 7, 2 9 P. regina. 
No. 8, 3 (P. regina 2 9 J C. macellaria 1 9 )• 
No. 9, none. 
No. 10, 4 (P. regina 1 cT, 2 9 ; C. macellaria 1 9 )• 
No. 11,2 (P. regina 1 C. macellaria 1 9 )• 
No. 12, 3 (P. regina 2 9 ; M. domesiica 1 9 )• 
No. 13, 3 (P. regina 2 9 ; C. macellaria 1 9 )• 
No. 14 to 18, 7 (P. regina 4 9 ; C. macellaria 2 9 ; -A/, domesiica 1 9 )• 
It is noteworthy that while the percentage of the three species recov¬ 
ered was estimated at the time of liberation to be Musca domesiica 7, 
Chrysomya macellaria 70, Phormia regina 22, the percentage of these spe¬ 
cies as recovered was approximately M. domesiica 14, C. macellaria 16, 
P. regina 70. At first sight this might lead one to think that P. regina 
was more prone to migration than C. macellaria; however, when we group 
the first four traps, which were from 930 to 2,588 feet from the point of 
liberation, and the last 14, which were from 2,123 to 3,076 feet, exactly 
50 per cent of the total number of marked C. macellaria recovered were 
in the more distant traps while the percentage of marked P. regina was 
but slightly over 30.5. Comparing the house flies in the same way, 
about 22 per cent were taken in the more distant group of traps. Atten¬ 
tion might also be called to the fact that of the 126 marked flies recovered 
only 6, or 4.75 per cent, were males. The percentage of the sexes of the 
flies liberated was not determined, but in the usual catch the number of 
males is much greater than this. Five of these males were taken in the 
four nearest traps, which might further suggest that the tendency to 
distant dissemination is more marked in the females. 
