130 ANIMAL ECOLOGY 



1912. The Influence of Hibernation and Migration on Animal 

 Parasites. Proc. Seventh Inter. Zool. Cong., Boston, 

 1907, pp. 673-684. 



WASMANN, E. 



1894. Kritisches Verzeichniss der Myrmekophilen und Termi- 



tophilen Arthropoden. pp. 231. Berlin. 

 A list of Arthropods found living with ants and termites. 



WEBSTER, F. M. 



1903. Notes upon the Food of Predaceous Beetles. Bull. 111. 

 State Lab. Nat. Hist., Second Edition, Vol. I, pp. 

 162-166. 



WEED, C. M., and DEARBORN, N. 



1903. Birds in their Relations to Man. pp. 380. Phila. 

 Extensive bibliography on the food of birds. 



WHEELER, W. M. 



1911. Insect Parasitism and its Peculiarities. Pop. Sci. 



Mo., Vol. LXXIX, pp. 431-449. 

 1910. The Effects of Parasitic and Other Kinds of Castration 



in Insects. Jour. Exp. Zool., Vol. VIH, pp. 377- 



438. 



ZACHARIAS, O., and others. 



1891. Die Tier- und Pflanzenwelt des Siisswassers. Bd. I, 



pp. 380 ; Bd. II, pp. 369. Leipzig. 

 Contains several valuable and suggestive papers on 

 the general biological relations of fresh-water plants 

 and animals. 



2. The Dynamic Relations of Aggregations and Associations, with 

 Special Reference to Animal Associations 



"A group or association of animals or plants is like a single 

 organism in the fact that it brings to bear upon the outer world 

 only the surplus of forces remaining after all conflicts interior 

 to itself have been adjusted. Whatever expenditure of energy 

 is necessary to maintain the existing internal balance amounts 



