INSECT POWDER 63 
the authors call pyrethrotoxic acid. Injected into guinea pigs, this 
acid produced its action in two perfectly distinct stages. In the first, 
an excitation was produced, being more or less pronounced according 
to the proportion of matter administered; in the second stage, on 
the contrary, a complete prostration was produced, accompanied 
always with paralysis of the lower extremities. 
Thoms (275), 1890, extracted 10 kilograms of best ‘‘closed” 
Dalmatian flowers with 55° petroleum ether for seven days. Evap- 
orated wn vacuo, he obtained 230 grams of a greenish yellow extract 
which had the characteristic odor of insect powder. This extract 
contained many crystals and was of a waxy consistency. By solu- 
tion in alcohol and again evaporating, a yellow wax, melting point 
54°C., was obtained. By pouring the alcoholic solution into water 
and setting in the direct sunlight, a white wax, of melting point 
56.5°, was obtained. After separation of the waxy bodies from 
the solution a sugar (dextrose) was shown to be present. Al- 
together, Thoms succeeded in isolating from insect powder: (1) An 
essential oil, (2) a volatile acid, (3) a wax, (4) anonvolatile, potassium 
permanganate reducing, balsamlike acid, (5) chlorophyll, (6) colo- 
phonic acid, (7) tannic acid, (8) a body with alkaloidal properties, 
(9) a body with glucosidal properties, and (10) sugar. Thoms found 
the petroleum-ether extract and the essential oil to possess toxic 
properties, while the nonvolatile acid, the glucoside, and the other 
substances were harmless to insects. 
De Boisse (64), 1895, claimed that the active principle of Pyre- 
thrum cinerariefolium is a yellow resin soluble in sulphuric ether, in- 
soluble in water, and very slightly soluble in alcohol, carbon disulphid, 
and fatty bodies. Alkalis decompose it rapidly. The flowermg 
heads and leaves contain a good deal of this resin; the lower parts of 
the stems, very little. De Boisse gives no experimental proof for 
these statements. 
Durrant (73), in 1897, stated: ‘‘ The toxic properties of insect _pow- 
der are due to (1) a volatile oil amounting to 0.5 per cent in picked 
specimens of closed flowers and much less in open flowers; (2) a soft 
acid resinous body which is the principle source of the toxic effect. 
It is found to the amount of 4.8 per cent in selected closed flowers, 
less than 4 per cent in half-open dower and still less in flowers that 
are fully open; the whole plant apart from the flowers contains mere 
traces of resin.” 
Gerard (93), 1898, stated that the active principle of Pyrethrum 
consists of an oleo-resin and an essential oil. These are found prin- 
cipally in the bracts and around the ovaries of the flowers, com- 
paratively little being present in the corollas. 
Sato (236, 237), as a result of work done in 1905-1907, reports the 
isolation of a light-yellow, odorless, transparent, sirupy resin from 
Pyrethrum flowers, which he calls pyretol. At first this is tasteless, 
‘but later has a benumbing effect. 1t is insoluble in water and dilute 
acids, and soluble in alcohol, ether, and petroleum ether. It is 
soluble in hot alkaline solutions, but when precipitated from such 
solutions by acids the resin becomes completely inactive. 
Fujitani (89), in 1909, conducted an elaborate research on the flow- 
ers of Chrysanthemum cinerarizfolium, using flowers cultivated in 
__ the provinces of Ki-i and Mikawa, Japan. The flowers were ground 
and the powder soaked for one week in 95 per cent alcohol at room 
temperature. The alcohol was distilled off, leaving an extract of a 
