-52- 
DeSussy et al. (48) in 1936 reported that Hyooderma tovis end 
H. lineaton can best be controlled by washing the animals with a 
suspension of derris in water. 
Wells ( 309 ) in 1937 sutmitted the following table shewing results 
of oreliminary tests et Colorado Sorin^s, Colo., in which rotenone, 
derri? powder, and devil 1 s-shoestrings were used against larvae of 
Hyqoderma lineatum encysted in the backs' of cattle. 
Four animals were treated externally with undiluted devil' s- 
shoestrings (1.72 percent rotenone) at the rate of 3 ounces oer animal, 
with the result thet of the 288 encysted larvae 250, or 86.8 percent, 
survived. On one animal, given an external application of 3 ounces 
of undiluted derris powder (3 percent rotenone), 51.11 percent of the 
90 encysted larvae survived. 
R. W. w ells, in a typewritten renort to the Division of Insects 
Affecting Man and Animals, Bureau of Entomology and Flant Quarantine, 
United States Department of Agriculture, in March 1937 on the control 
of Hvpoderme lineatum lervae in the backs of cattle in Colorado, Mis- 
souri, and Iowa, stated that in 1°34 it was found that a treatment 
with e solution mede up with 70 cc. of paraffin oil, 5 cc. of cresol, 
25 cc. of benzol, and carrying 1 sm. of rotenone to each 100 cc. of 
the composite solvent, was survived by only 5.59 percent of the larvae 
treated (by injection into the cyst), whereas the seme solvent without 
rotenone was survived by 75.47 percent of the larvae treated. Numerous 
tests led to the conclusion thet 1 gr<.. of rotenone per 100 cc. of 
Method of 
: C 
omnosition 
of 
solut 
ion 
/Animals 
• Larvae 
• Larvae 
treatment 
: '0il 
Cc. 
! Cr 
esol 
Co. 
ll 
5nzo 
1 1 Ro 
tenone 
"! treated 
: treated 
: survivi 
-ng 
8c. 
§a. 
Number 
Number 
Number 
Percent 
External 
45 
5 
50 
3.0 
14 
317 
10 
3.15 . 
Injection 
45 
5 
50 
1.0 
4 
. 115 
7 
6.08 
Do. 
70 
5 
25 
1.5 
2 
52 
4 
7.67 
Do. 
70 
5 
25 
•0.5 
9 
211 
11 
5.21 
Do. 
' 70 
5 
25 
: 1.0 
20 
234 
17 
7.26 
Do. 
' 70 
5 
25 
0.5 
7 
135 
15 
11.11 
Cr 
esol 
com- 
„ 
uound 
Do. 
45 
5 
50 
0.5 
10 
202 
31 
15.34 
Cresol 
.com- 
pound 
