294 CAUSES OF VARIATION 



ADDITIONAL REFERENCES 



CERTAIN HABITS OF ANIMALS TRACED TO THE ARRANGEMENT OF 

 THEIR HAIR. By Walter Kidd. Proceedings of the Zoological Society 

 of London, II, 145-158. 



EFFECT OF CLIMATE ON SUGAR CONTENT OF BEETS. Experiment Station 

 Record, XIII, 736. 



EFFECT OF DARKNESS UPON VEGETATION. Experiment Station Record, 



XIII, 651. 



EFFECT OF ELECTRICITY UPON GROWTH OF PLANTS. Experiment 



Station Record, XIV, 346, 352, 548 ; (Acetylene Gas Light), XIV, 



421, 437; XVI, 137. 

 EFFECT OF HUMIDITY ON GROWTH. Experiment Station Record, XII, 



1014. 

 EFFECT OF PRESENCE OR ABSENCE OF CERTAIN SALTS UPON THE 



COMPOSITION OF THE CROP. Experiment Station Record, XIV, 



561-563. 

 EFFECT OF STARVATION ON PLANT GROWTH (first, shortage of nitrogen ; 



second, shortage of potassium). Experiment Station Record, XIV, 



H9. 347- 

 EFFECT OF WATER CONTENT UPON DEVELOPMENT OF WHEAT, OATS, 



CLOVER, ETC. Experiment Station Record, XIII, 125-126, 441-631. 

 EXPERIMENTAL ZOOLOGY. By J. H. Morgan. Chapters II and III, 



pp. 1 2-4 1. 1 

 INJURIOUS EFFECT OF FREEZING ON DEVELOPMENT OF THE EMBRYO 



IN THE EGG OF THE HEN. Experiment Station Record, XI, 577. 

 VARIATION OF ANTHRAX BACILLUS WHEN BRED UNDER DIFFERENT 



CONDITIONS. Experiment Station Record, XIV, 293, 916. 

 VARIATION IN NITROGEN CONTENT OF WHEAT. Experiment Station 



Record, XIII, 451. 



VARIATION IN TUBERCLE BACILLI WHEN FOUND IN DIFFERENT ENVI- 

 RONMENT. Experiment Station Record, XIV, 1121 ; XV, 188. 

 VARIATIONS CAUSED BY FERTILIZATION. Experiment Station Record, 



XIV, 347. 



1 This excellent volume was not yet off the press when this copy was prepared. 

 It is especially recommended. 



