78 BULLETIN 824, TJ. S. DEPAETMENT OF AGEICULTUEE. 
the material. That saponification with alcoholic potash effects chem- 
ical decomposition in some of the compounds present is also shown 
by the fact that petroleum ether added to the U. S. P. ether solution 
of the saponifiable portion precipitates a resin, whereas all the mate- 
rial before saponification was soluble in petroleum ether. 
Procedure 2. 
Since saponification with alcoholic potash destroys the insecticide! 
action of the material extracted by petroleum ether, another proce- 
dure was adopted. A petroleum-ether extract was obtained as be- 
fore, evaported to dryness, and taken up in TJ. S. P. ether. This 
ethereal solution was successively extracted with aqueous solutions 
of ammonium carbonate, sodium carbonate, and sodium hydroxid, 
made up on the basis of 10 grams of salt to 100 cc. of solution. The 
ammonium carbonate solution assumed a light yellow color when 
shaken with the ethereal solution of the extract. Emulsions which 
were difficult to separate formed. After repeatedly extracting with 
ammonium carbonate and washing with water, the ethereal solution 
was separated, and reserved for the sodium carbonate extraction. 
The ammonium carbonate solution was made acid with sulphuric 
acid and shaken with ether, which slowly and apparently incom- 
pletely took out the yellow color. On evaporating this ether extract 
to dryness, after washing and drying over calcium chlorid, a few 
greenish-yellow, oily, sticky drops were left. From 1,920 grams of 
powdered flowers only 0.345 gram of material was thus obtained. 
This amount was too small for purification and chemical testing, and 
was, therefore, used for testing on insects. It was dissolved in about 
50 cc. of 95 per cent alcohol, diluted with an equal quantity of water, 
and sprayed on nasturtium plants which were infested with aphides. 
From 75 to 80 per cent of the aphides were killed. In check tests 
with 50 per cent alcohol no aphides were killed. 
The aqueous solution of sodium carbonate removed a noticeable 
amount of a brownish-yellow material, which was obtained as a 
sticky mass after acidifying and extracting with ether. Tested 
against aphides in the same way, the material proved to be very ac- 
tive, killing 100 per cent. Extraction with sodium hydroxid solu- 
tion removed a quantity of chlorophyll and also some of the insec- 
ticidal constituents. About 80 per cent of the aphides sprayed with 
an aqueous alcoholic emulsion of the extracted material were killed. 
On evaporating the ethereal solution of the original petroleum-ether 
extract after these successive extractions with aqueous ammonium 
carbonate, sodium carbonate, and sodium hydroxid, a strong reddish- 
orange pasty material was left. Tested on aphides, this material 
likewise exhibited marked insecticidal power, killing about 90 per 
cent of the insects. 
