18 BULLETIN 824, U. S. DEPARTMENT OF AGRICULTURE 
ining insect powders, made use of Kalbruner s “fly test.”” He, how- 
ever, used a weighed quantity of powder placed on a sheet of white 
paper, over which the insect was imprisoned with a glass. Tested 
against Blatta orientalis (Oriental cockroach or black beetle) and 
Acarus faring in this manner, the powder from both the P. cinerariz-_ 
folium and the P. roseum killed the insects in about 45 minutes. 
About the same time, Goff (104) made tests with P. cinerarizfolium 
srown in California and a powder prepared from the flowers of 
Pyrethrum roseum, grown in New York from seed received from the 
United States Department of Agriculture, to determine the relative 
time required to paralyze flies. These tests indicated that the 
powder made from P. roseum was slightly more effective. 
Hirschsohn (133), in 1890, while investigating the active constitu- 
ent of insect powder, tested the activity of the powder by trying it on 
roaches. ‘Two of the samples under investigation paralyzed roaches 
in 3 minutes. From his tests on Blatta orientalis, Thoms (275) con- 
cluded that the physiological test was surer than either the micro- 
scopical or chemical test in estimating the worth of a powder. 
In 1895, Jelliffe (148) tested the action of insect powder on the 
common house fly (Musca domestica), the Croton bug or cockroach 
(Blatta germanica), the bedbug (Cimesx lectutarius), and some black 
beetles (species undetermined). 
Dowzard (71), in 1899, conducted some tests on cockroaches. 
Slaus-Kantschieder (261), in 1913, stated that although the micro- 
scepical and chemical methods of examination furnish a basis for the 
grading of insect powder, for the determination of the true value the 
physiological test must be made. He conducts the test as follows: 
About i gram of insect powder is placed in a 25 cc. flask. The flask 
is then closed and shaken well, after which the flies are introduced. If 
the powder is of good quality the flies will come to rest within one- 
half minute and die within 5 minutes. If the flies survive this 
period the insect powder is to be considered as of low value and old. 
Kuraz (165) has recently tested a number of commercial samples of 
insect powder, as well as closed, half-closed, and open flowers, and 
Pyrethrum stems grown at Korneuburg, near Vienna, according to 
the method of Slaus-Kantschieder. The ordinary house fly ( Musca 
domestica) was used in these tests, and the time noted in which the 
insect fell over on its back. The results are summarized in Table 2. 
TABLE 2.—Physiological examination of insect powder } 
Time required 
Product Mini- Maxi- 
aera mai Average 
Min. Sec.| Min. Sec.| Min. Sec. 
0 40 45 0 
Commercial powder ground from wild flowers_-.-...-_.-.---------------- 1 9 
Commercial powder ground from Montenegrin closed flowers____-__----_- 1 04} 2 ARS eas 43 
Commercial powder ground from Dalmatian half-closed flowers_______---_- 1 00} 2 22a: 34 
Commercial powder ground from Dalmatian open flowers_-_-___-_--__-_-_--- Re 03 | 4 Zi <3 00 
Commercial spow ders 2 22 cies er ee ey ee eee 5 50 | 15 14 | 10 05 
Commercial powder ground from open Dalmatian flowers____.__-_-___--- 2 20| 4 DOE eo 28 
Commercial powder ground from closed Dalmatian flowers__-_..-.------- 0 45 | 1 DD |e 18 
Commercial powder ground from closed Montenegrin flowers___---------- Of 403i crak 34] 1 04 
COMMERCIAL POW GET ee we oe ee Re aga ete lee Mate ae nena nny Le tae een ee 3 52 | 10 00 | 6 02 
Powdered closed flowers grown at Korneuburg, 1913__.__-_-_------------- 1: 9220) S22 ee Souh el 53 
Powdered half-open flowers grown at Korneuburg, 1913__-_-_---_--------- 0 54] 1 48; 1 18 
Powdered closed flowers grown at Korneuburg, 1914_________-_-.--------_- 0 Os45:)tal 43} 1 10 
Powdered half-open flowers grown at Korneuburg, 1914__....____._______- 0 40} 1 45 bel 15 
Powdered open flowers grown at Korneuburg, 1914________-_-_-___-_----- 0 40 |} 1 28} 1 02 
Powdered stems grown at Korneuburg, 1914__..-_.-.---.----------------- 3), 05s} p8e A294 e26 16 
150 tests were made on each sample, 
