A study in applied ecology. One of the best detailed studies of the birds of a small tract of land and their ecological relations. STAHL, E. 1888. Pflanzen und Schnecken. Biologische Studie über die Schutzmittel der Pflanzen gegen Schneckenfrass. Jena. Zeitschr. für Naturwiss. herausgegeben von der med.-naturwiss. Gesell. zu Jena, Bd. XXII, pp. 557-684. A study of the means by which plants are protected(?) from snails and slugs. Numerous feeding experiments. DAHL, F. 1908. Die Lycosiden oder Wolfspinnen Deutschlands und ihre Stellung im Haushalte der Natur. Nova Acta der Ksl. Leop.-Carol.-Deutschen Akad. der Naturf., Bd. LXXXVII, pp. 175-678. Halle. Not seen by writer. Mr. J. H. Emerton writes that this paper “gives tables of comparative collecting in all kinds of country.” PIERCE, W. D., CUSHMAN, R. A., and HOOD, C. E. 1912. The Insect Enemies of the Cotton Boll Weevil. U. S. Dept. Agr., Bur. Ent., Bull. No. 100. pp. 99. An excellent example of the character of the competition with which an animal meets when extending its range into new territory. See diagram, p. 44. WHEELER, W. M. 1906. An Ethological Study of Certain Maladjustments in the Relations of Ants to Plants. Bull. Amer. Mus. Nat. Hist., Vol. XXII, pp. 403-418. Competition between plants and ants. MASSART, J., and VANDERVELDE, E. (Trans. W. MACDONALD.) 1907. Parasitism Organic and Social. Second Edition. Revised by J. Arthur Thompson, pp. 124. London. Contains many examples of responses to a parasitic environment. _Selected References on the Struggle for Existence_ (Alphabetically arranged) BEAL, F. E. L. 1911. Food of the Woodpeckers of the United States. U. S. Dept. Agr., Bur. Biol. Surv., Bull. 37. pp. 64. CHAPMAN, F. M. 1902. The Economic Value of Birds to the State. Seventh Rep. N. Y. Forest, Fish, and Game Comm., 1901, pp. 115-176. Reprint, pp. 66, 1903. Albany. Contains an extensive list of papers on the food of birds. EICHELBAUM, E. 1910. Über Nahrung und Ernährungsorgane von Echinodermen. Wiss. Meeruntersuch. heraus. von der Komm. zur wiss. Unter. der deutsch. Meere in Kiel. N. F. Bd. XI, Abth. Kiel, pp. 187-275. FORBES, S. A. 1883. The Food Relations of Predaceous Beetles. Twelfth Rep. State Ent. Ill., pp. 105-120. 1903. The Food of Birds. Bull. Ill. State Lab. Nat. Hist., Second Edition, Vol. I, pp. 86-161. 1903. Notes on Insectivorous Coleoptera. Bull. Ill. State Lab. Nat. Hist., Second Edition, Vol. I, pp. 167-176. 1883. The Food Relations of the Carabidæ and Coccinellidæ. Bull. Ill. State Lab. Nat. Hist., Vol. I, No. 6, pp. 33-64. FORBUSH, E. H. 1907. Useful Birds and their Protection. Mass. State Board Agr. pp. 437. Boston. FOREL, A. 1896. Ants’ Nests. Smithsonian Report for 1894, pp. 479-505. Ants’ nests, and symbiosis between plants and ants. GAMBLE, F. W., and KEEBLE, F. 1903. The Bionomics of _Convoluta roscoffensis_ with Special Reference to its Green Cells. Quart. Jour. Micros. Sci., Vol. XLVII, pp. 363-431.