October, '19] ABBOTT: NAPHTHALENE VS. CHICKEN LICE 397 



together and two of the same color mating. These two color forms 

 have been known as separate varieties, stevensi Baly and plagiatus 

 Melsh. They mated and deposited eggs during the last half of July. 



The eggs were laid in moist earth just below the surface of the 

 ground. One mass was found to contain nineteen eggs glued together 

 with a viscous covering. The egg is elliptical in form, is 0.65 mm. 

 long and 0.3 mm. broad at the middle. It is smooth and a glistening 

 white in color. 



The larvae have not yet been found but probably live in the ground 

 and feed upon the roots of plants. 



References 

 1849. Melsheimer, Dr. F. E. Descriptions of New Species of Coleoptera of the 



United States. Proc. Phil. Acad. Sci., 3: 169. 

 1865. Stauffer, J. A New Grape-vine Enemy. Gardener's Monthly, Aug. 1865, 



p. 233-4. 

 1890. Packard, A. S. Fifth Report U. S. Ent. Comm., p. 328. 

 1899. Smith, J. B. Insects of New Jersey, p. 304. 

 1910. Blatchley, W. S. Coleoptera of Indiana, p. 1142. 



NAPHTHALENE VS. CHICKEN LICE^ 



By W. S. Abbott, Bureau of Entomology 



In connection with the work of testing proprietary insecticides and 

 their ingredients, which is carried on at the Insecticide Board's Testing 

 Laboratory located at Vienna, Va., a considerable amount of data has 

 been obtained on the value of naphthalene as a chicken lice remedy. 

 These experiments have been summarized, and since much of this 

 data is new they are presented here in the hope that they may be of 

 value to economic entomologists who are interested in this line of 

 work. 



Naphthalene is a very common ingredient in proprietary lice pow- 

 ders, occurring in those tested in quantities ranging from .17 per cent 

 to 67 per cent. It is also found on the market moulded into the form 

 of nest eggs which may be pure naphthalene or naphthalene mixed 

 with paraffin, clay, plaster, etc. 



The hens used in these tests were of no particular breed or age, and 

 were all moderately to badly infested with chicken lice of several 

 species. The common l)ody louse, Mcnopon biscriatum Paiget, was 

 the most abundant, but M. -pallidum Nit., Lipcnrus hcterographus 

 Nit., and Goniocotes ahdominalis Paig., were often present. 



'Publishod with the consent of the Secretary of the U. S. Department of .\gri- 

 culture. 



