INSECT POWDER. 



65 



phosphorus pentoxid of C. roseum correspond closely to those of the 

 closed flowers of C. cinerarisefolium. The powder prepared from the 

 flowers of C. roseum is much darker and has a different odor than the 

 ordinary insect powder. The odor of an insect powder and a micro- 

 scopical examination should serve as a means to determine whether 

 or not the product has been prepared from C. roseum or C. cine- 

 rarisefolium. 



Table 43. — Analysis of insect flowers {Chrysanthemum roseum). 



Sample No. 



Nitrogen, 



N. 



TjOs. 



F:ther 

 extract. 



Pento- 

 sans. 



Crude 

 fiber. 



Ash. 



Ash 

 insohible 

 in HCl. 



17S79 



Per cent. 

 2.08 

 2.08 

 2.26 

 1.95 

 2.04 

 1.97 

 2.08 

 2.00 



Per cent. 



Per cent. 



Per cent. 



Per cent. 



Per cent. 

 8.75 

 8.45 

 11.09 

 10.89 

 11.90 

 12.62 

 9.15 

 9.88 



Per cent. 

 0.00 



ISOl 1 











.35 



20487 



0.714 

 .691 



.738 



2.83 

 2.74 

 2.73 



13.78 

 13.21 

 13.42 



20.44 

 20.04 

 19.31 



1.11 



21737 



1.45 



22070 



1.51 



22295 



3.42 



22575 



.640 

 .581 







18.46 

 17.80 



.45 



22693 . 







1.26 













1.95 

 2.26 

 2.08 



.691 

 .738 

 .714 



2.73 

 2.83 

 2.77 



13.21 



13.78 

 13.47 



19.31 

 20.44 

 19.93 



8.45 

 12. 62 

 10.34 



.35 





3.42 





1.27 







Samples of CJirysanthemum- leucanthemum (generally called "field 

 daisy" or "oxeye daisy" in this country), which have been largely 

 used in. the past, and to some extent at the present time,^ as an 

 adulterant of insect powder, have been analyzed in the Insecticide 

 and Fungicide Laboratory (Table 44). 



Table 44. — Analysis of Chrysanthemum, Icucantheviuvi. 



Sample 

 No. 



Description. 



Nitrogen, 



N. 



Ash. 



Ash 

 insoluble 

 inHCl. 



P2O6. 



Kther 

 extract. 



Pento- 

 sans. 



Crude 

 fiber. 



» 14933 



Flowers only 



Per cent. 

 1.82 

 2.23 



Per cent. 

 10.02 

 10.45 

 10.38 



Per cent. 



0.92 



.15 



.15 



Per cent. 

 0. 684 



Per cent. 

 3.18 



Per cent. 

 14.34 



Per cent. 

 20.14 



2 23020 



do 





23020 



Stems only i 1.45 

























I Sent in as "false" insect flowers. 



2 Collected near Markham, Va. 



ACTIVE PRINCIPLE OF INSECT POWDER. 



PREVIOUS INVESTIGATIONS. 



The earliest recorded investigation on the active insecticidal con- 

 stituents of insect powder is that of Ragazzini cited by de Visiani 

 (67) in 1854. The powder prepared from the Chrysanthemum cinera- 

 rixfolium was used by Ragazzini in his experiments. His conclusion 

 was that the narcotic action of the powder was due not to any 

 single substance but rather to a mixture of substances. 



1 U. S. Dept. Agr. Bull. 795. 

 139815°— 20— Bull. 824 5 



