42 
BIBLIOGRAPHY OF ECONOMIC ENTOMOLOGY. 
506. Holder, C. F. Insect migration. <Sci. Amer., 1 April, 1899, 
p. 996, 1 tig. 
Grasshoppers in the West. 
507. Holland, W. J. Concerning ticks. <Can. Entoin., April, 
1898, pp. 96-97. 
508. Hopkins, A. D. Preliminary report on the insect enemies of 
forests in the Northwest. <Bull. No. 21, n. s., Div. Ent., 
U. S. Dept. Agric., December, 1899, pp. 27. 
Notes on the habits of many forest insects. 
509. Hopkins, A. D. The San Jose or pernicious scale. <W. Va. 
Farm Reporter, 1897, pp. 84-86. 
510. Hopkins, A. D. Entomology and the entomologist as related to 
horticulture and the horticulturist. < W. Va. Farm Reporter, 
December, 1897, pp. 411-413. 
511. Hopkins, A. D. The periodical' cicada in West Virginia. 
<Bull. No. 50, W. Va. Agric. Exp. Sta., January, 1898, pp. 
46, 23 tigs., 1 map. 
Treats also of damage by tree crickets and woolly aphis. 
512. Hopkins, A. D. On the history and habits of the “wood 
engraver *’ ambrosia beetle, Xyleborus xylograjphicus Say, 
{Xyleborus saxeseni Ratz.), with brief descriptions of different 
stages. <Can. Entom., February, 1898, pp. 21-29, 2 pis. 
513. Hopkins, A. D. Insect enemies of the locust tree. <W. Va. 
Farm Review, March, 1898, pp. 88-93, 6 tigs. 
Notes on Odontota dorsalis, O. nervosa , Cyllene robinise, and Prionoxystusrobinise. 
514. Hopkins, A. D. The San Jose scale in West Virginia. <W. 
Va. Farm Review, April, 1898, pp. 124-127. 
515. Hopkins, A. D. Some notes on observations in West Virginia. 
<Bull. No. 17, n. s., Div. Ent., IL S. Dept. Agric., Novem¬ 
ber, 1898, pp. 44-49. 
Short notices of various species. 
516. Hopkins, A. D. Insects detrimental and destructive to timber 
products. <Proc. 19th Ann. Meet. Soc. Prom. Agric. Sci., 
1898, pp. 103-108. 
Treats of Scolytus 4-spinoms, Dendroctonus frontalis, Melanophila fulvoguttata, 
Agrilus bilineatus, Lymexylon sericeum, Eupsalis minuta, Corthylus Columbia - 
nus, Lyctus striatus, and Phymatodes variabilis. 
517. Hopkins, A. D. Report of the entomologist. Cllth Ann. 
Rept. IV. Va. Agric. Exp. Sta., 1898, pp. 32-40. 
Summary of year’s work. 
518. Hopkins, A. D. Present outlook of the San Jose scale problem. 
<W. Va. Farm Reporter, April, 1899, pp. 76-79. 
