NATURE'S CRAFTSMEN 



1902 brood was predicted, and it arrived "on time." 

 If readers will make note of the cicadas' coming in their 

 own neighborhood, they may be sure that seventeen 

 years thereafter another brood will appear. There is, 

 however, a thirteen-year brood which must be allowed 

 for, at times. But there is no need to consider here 

 that exceptional incident. 



We begin our history with the exode of the pupae 

 from the ground, and will limit it to observations of 

 the brood of 1885 in Philadelphia. The first pupse ap- 

 peared about May 23, but were not out in great num- 

 bers until the second week in June. The exode began 

 about six o'clock, evening, and continued during the 

 night, but chiefly the first part thereof. The exit from 

 the burrow was deliberate, as was also the insect's 

 progress over the surfaces on which they travelled. 

 They moved forward and upward without manifest di- 

 recting purpose, but with a general tendency to get as 

 far up as possible. They paused at various distances 

 from the ground, and attached themselves to sundry 

 parts of trees and other objects. More than a dozen 

 pupa-cases were seen cUnging to the leaves of a small 

 twig eight inches long. Apparently, where the uncon- 

 trollable sense of their coming transformation arrested 

 them, there they halted, obedient to that Overforce that 

 brooks no denial from any creature. 



On the evening of June 4th great numbers were 

 ascending tree-trunks in a neighbor's spacious grounds. 

 They had directed their course towards the trees from 

 all parts of the lot, but an adjacent fence received a 

 portion of the host. They issued in such numbers that 

 trunks, branches, and leaves of trees were covered with 

 them, in motion or at rest. The ground beneath was 



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