Nuttall ^ says: ''The Red-eyed Vireo is one of the most favor- 

 ite of all the adopted nurses of the Cowbird ; and the remarkable 



gentleness of its disposition and watchful affection for the safety 

 of its young, or the foundling confided to its care, amply justifies 

 this selection of a foster parent. ' ' 



The same author also says : ^ " The most usual nurse of this 

 bird seems to be the Red-eyed Vireo, who commences sitting as 

 soon as the Cowbird 's egg is deposited." He also suggests, in 

 effect, that the incubation period of the Cowbird is shorter than 

 that of the Vireo (page 107). This question should be easy of 

 determination under favorable circumstances, and is important. 

 If the Cowbird deposits her egg in a nest before the other eggs 

 are laid, the rightful owner is more likely to desert. If the nest 

 already contains a clutch of eggs, then the shorter incubation 

 period for the parasite Avould be a yery decided advantage. 



Instinct or Intelligence * 



Coues ^ has attempted an analysis of the beha^dor of the right- 

 ful owners of a nest after the intrusion of a Cowbird 's egg, and 

 his evident conclusion is that they are usually conscious of the 

 imposition, and intelligently decide to make the best of it. Or 

 that when the parasitic egg is buried under a superstructure, it 

 is indicative of a mental faculty analogous to human reason. 

 Coues states that ''instinct is a lower order of reason," which 

 view may be in harmony ^^-ith the present views of behaviorists, 

 insofar that the development of instincts precedes that of the 

 reasoning faculty; and that intelligent behavior may in some 

 organisms control instinctive behavior, and in the higher organ- 



® Op. cit., page 182. 

 ^Ibid., page 107. 



* In the discussion of this topic the writer is guided by the interpretation of animal 

 behavior as recently set forth by Parmalee in "The Science of Human Behavior." 

 According to this interpretation the simplest form of behavior is the tropism — a 

 direct and predictable motor response of an organism to an external stimulus. Next 

 in order is the reflex arc — similar in action to the tropism, but operating only in 

 the specialized tissues of the nervous system. An instinct is defined as "an inherited 

 combination of reflexes which have been integrated by the central nervous system 

 so as to cause an external activity of the organism -which usually characterizes a 

 whole species and is usually adaptive." Intelligent action is based upon experience 

 and depends upon associative memory. "Intelligent behavior is therefore made up 

 of tropic, reflex, and instinctive actions which have been combined in new ways as a 

 result of experience so as to constitute new forms of behavior." (Page 258). In- 

 telligent action depends upon the development of the association areas in the central 

 nervous system, by means of which experience, or past images, may be used as stimuli. 

 ® Birds of the Northwest. By Elliott Coues. Washington, 1S74. Pages 180-186. 



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