REFERENCES TO SCIENTIFIC TECHNIQUE 59 



and bird tracks or foot prints. Devoted mainly to 

 game and fur-bearing animals. Very valuable to 

 the student of live animals in nature. Many of 

 our smaller species are worthy of similar treatment. 



BtTRNS, F. L. 



1901. A Sectional Bird Census. Wilson Bulletin, N. S., 



Vol. VHI, pp. 84-103. 



A quantitative study of the birds found breeding on 

 an area of one square mile. Other similar studies 

 should be made. 



CHAPMAN, F. M. 



1900. Bird Studies with a Camera. With Introductory 



Chapters on the Outfit and Methods of the Bird 

 Photographer, pp. 218. New York. 

 The title clearly indicates the character of this book. 



COMSTOCK, J. H. 



1897. Insect Life. pp. 349. New York. 

 Directions for the study of insects. 



CLEMENTS, F. E. 



1905. Research Methods in Ecology, pp. 334. Lincoln, 



Nebraska. 



Important for methods of study in plant ecology, 

 partly also applicable to animals ; photography, and 

 instruments for the study of environments. 

 DAHL, F. 



1901. Was ist ein Experiment, was Statistik in der Ethologie ? 



Biol. Centralbl., Bd. XXI, pp. 675-681. 

 1903. Winke flir ein wissenschaftlicher Sammeln von Thieren. 

 Sitzungs-Ber. der Gesell. naturfor. Freunde zu 

 Berlin. Jahrg. 1903, pp. 444-475. 

 This contains, in addition to its suggestions on collect- 

 ing, an interesting outline or classification of animal 

 habitats (Cf. also Enderlein, 1908, pp. 72-77). 

 This is not a genetic classification. Dahl's list of 

 habitats will prove very suggestive to the student 



