EMULSION'S FOE JAPANESE BEETLE 3 



Table 1. — Results obtained from dipping third-instar larvae of the Japanese beetle 



in various solutions 



Compound 



Concentration of 

 solution 



Larvae ' 



dipped 



Propor- 

 . tion of 







Time in 



Propor- 

 tion 

 killed 



larvae 

 killed 



dip 



in soil 2 



Hours 



Per cent 



Per cent 



2 











6 



100 



100 





100 



75 





66 



















100 



100 



l A 



100 



100 





100 



























































100 



90 





100 



33 



Effect of solution 

 on plants 3 



Zinc chloride 



Wormseed oil 



Alpha napthoL 



Benzaldehyde 



Beta-napthol benzoate. 



Carbon disulfide 



Carbon disulfide 



Formaldehyde 



Furfural 



Mercuric chloride 



Paraldehyde 



Pyridine 



Petroleum ether 



Thymol.- 



Toluene 



5 per cent 



Saturated 



do 



do 



do 



X A saturated. . 



Saturated 



5 per cent 



3 per cent 



0. 1 per cent 



8 per cent 



3 per cent 



Saturated 



do 



..._do 



Killed. 

 Slight check. 

 Killed. 



Do. 

 Normal. 



Checked somewhat. 

 Checked badly. 

 Killed. 



Do. 

 Injured badly. 

 Killed. 



Do. 

 Normal. 



Checked considerably. 

 Checked. 



1 Larvae not in soil. 



8 Larvae in pots of soil (light sandy loam) watered with a volume of the solution equal to the volume of 

 the soil. 

 ' Salvia, aster, nasturtium, and chrysanthemum. 



OIL OF WORMSEED (AMERICAN) 



American wormseed oil (oelum clienopodii anthelmintici) is distilled 

 in Carroll County, Md., from the entire cultivated plant of OJieno- 

 podium ambrosioides anthelminticum Linne (family Cnenopodiaceae). 



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, ct-terpinene 5 per cent, and a new laevorota- 

 tory terpene, 10 per cent. 



Practically 4 pure ascaridole can bo separated from oil of worm- 

 seed by a fairly easy process (4). The oil is fractionated under 

 vacuum, the heat being kept low, for wormseed oil or, specifically, 



'The figures (italic) in parentheses refer to " Literature cited," p. 17. 

 1 From correspondence with O. A. Russell. 



