EMULSIONS FOE JAPANESE BEETLE 3 
Table 1. — Results obtained from dipping third-instar larvse of the Japanese beetle 
in various solutions 
Concentration of 
solution 
Larvse ' dipped 
Propor- 
tion of 
larvae 
killed 
in soil 2 
Compound 
Time in 
dip 
Propor- 
tion 
killed 
Effect of solution 
on plants 3 
Zinc chloride 
Hours 
2 
6 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Per cent 

100 
100 
66 

100 
100 
100 





100 
100 
Per cent 

100 
75 


100 
100 






90 
33 
Killed. 
Slight check. 
Killed. 
Alpha napthoL. 
.do . 
Benzaldehyde 
...do 
Do. 
Beta-napthol benzoate. 
....do 
Carbon disulfide ... .. 
Yi saturated 
Checked somewhat. 
Checked badly. 
Killed 
Furfural . . ... ... 
Do. 
Mercuric chloride __ ... 
0.1 per cent 
Injured badly. 
Paraldehyde 
Killed. 
Pyridine... . ... 
Do. 
Petroleum ether. . . 
Saturated. . 
Thymol 
do 
do 
Checked considerably. 
Checked. 
1 Larvae not in soil. 
2 Larvae in pots of soil (light sandy loam) watered with a volume of the solution equal to the volume of 
the soil. 
5 Salvia, aster, nasturtium, and chrysanthemum. 
OIL OF WORMSEED (AMERICAN) 
American wormseed oil (oelum chenopodii anthelmintici) is distilled 
in Carroll County, Md., from the entire cultivated plant of Cheno- 
f odium ambrosioides antJielminticum Linne (family Chenopodiaceae). 
In the ninth edition of the U. S. Pharmacopoeia the oil of cheno- 
podium, or oil of American wormseed, is described as a volatile oil 
distilled from the above-named plant. The oil is colorless or pale 
yellow, soluble in 8 volumes of 70 per cent alcohol, and varying in 
specific gravity from 0.955 to 0.980 at 25° C. 
In recent years producers and dealers have urged that the U. S. P. 
standards for this oil should be lowered, basing their argument on the 
fact that authentic oils obtained at the stills do not come up to the 
standard. However, Russell (6)' s has shown conclusively that this 
shortcoming is due to faulty distillation, and that by distilling the 
herb with a large volume of steam during a relatively short period 
of time an oil can be produced that will meet all the U. S. P. require- 
ments. 
CHEMICAL COMPOSITION OF THE OIL 
American wormseed oil {2) contains minute quantities of the 
lower fatty acids, chiefly butyric acid, and less than 0.5 per cent of 
methyl salicylate. Of the remainder of the oil at least 60 per cent 
is ascaridole, with about 5 per cent of the corresponding glycol and 
30 to 40 per cent of a mixture of hydrocarbons made up approximately 
of cymene 15 per cent, a-terpinene 5 per cent, and a new laevorota- 
tory terpene, 10 per cent. 
Practically 4 pure ascaridole can be separated from oil of worm- 
seed by a fairly easy process (J/.). The oil is fractionated under 
vacuum, the heat being kept low, for wormseed oil or, specifically, 
3 The figures (italic) in parentheses refer to "Literature cited," p. 17. 
* From correspondence with G. A. Russell. 
