﻿114 FIELD AND FOREST. 



innate, spontaneous tendency to act, and not the result of an acquired 

 faculty through association, nor of an educated taste. 



II. — Nearly all birds modify their habitations to accord with exteral 

 influences. This is the result of experience. The original tendency to 

 act under the stimulus of sensations. Learning to make use of this 

 power to subserve necessary requirements, the bird often shows mar- 

 velous facility. So rapid frequently are these acquisitions, that it is 

 next to impossible to distinguish them on the one side, from undeni- 

 able iustincts; and, on the other, from certain forms of ratiocination. 



It will be seen that nothing more than a mere outline has been here 

 sketched. Experimental research into the more metaphysical portions 

 of the subject would throw much light upon the question of animal in- 

 stincts; and under more favorable circumstances of publication, it 

 may be brought forward again. 



David Scott. 

 Washington, D. C. 



Doryphora Decemlineata. 



Noticing a paragraph in a cotemporary journal, to the effect that 

 Sweden has prohibited the importation of potatoes into that country, 

 from England, Germany, France and the United States, recalls the 

 article on this subject in the October number of Field and Forest, p. 

 66, which describes an experience similar to my own in regard to the 

 insect named above. 



In July, 1875, I took a walk along the beach from Henlopen Light- 

 house to the extreme point of the Cape, a distance of about six miles. 

 I found many insects strewn along the water line of the beach, chiefly 

 Coleoptera, and among these, twenty-five to one, were the Colorado 

 potato-beetle. These were thrown upon the beach by the waves, 

 about one fourth of them still alive, and, singularly enough, I nearly 

 always found those travelling toward the water, instead of away from 

 it, indicating either great stupidity, or an instinctive determination to 

 continue their migrations eastward, at any hazard. Now, this part of 

 the beach is from three to four miles away from any cultivated ground, 

 or from any potato fields, the intervening space being sand hills and 

 flats, with here and there a sparse growth of stiff, wiry grass nothing 

 to the taste of these insects. Their migration over these flats and out 



