WATER-STRIDERS 



bobbing at the foot of the fall, and holding thereto 

 sways back and forth, under and out of the water for a 

 time, when I lose sight of her. . . . The storm is now 

 nearly over. It rumbles down the Chester Valley and 

 growls among the Valley Forge hills. The heavy rain 

 has dwindled to scattering drops. The sun looks out 

 from a bank of glowing clouds in the horizon. The 

 bells of Berwyn ring the Angelus. There is a sunburst; 

 the trees are gleaming as though studded with diamonds, 

 and there is a rainbow in the east." So end the field 

 notes for that day. 



I have saitl that the water-striders are among the 

 earliest heralds of the spring, appearing in March, if 

 the season is not too severe. I have an earlier record. 

 The close of January, 1906, brought some extraordinary 

 weather throughout much of the United States. Janu- 

 ary 20th to 23d were June days in temperature, the 

 thermometer rising to nearly 72° Fahrenheit at Brook- 

 camp. Many water-striders and a few whirligig beetles 

 appeared on our brook. The striders were all adults, 

 and they were rowing and leaping, and sporting, court- 

 ing, and mating as though summer were in full sway. 

 They had not disappeared from the waters until De- 

 cember 6th preceding. 



There soon came, of course, the inevitable retrogres- 

 sion to the natural - season temperature. But even 

 when the thermometer stood at or near the freezing- 

 point our boatmen kept afloat, showing unexpected 

 power to endure cold weather. But by - and - by the 

 chilly air proved too much for them, or, at least, for 

 their insect food supplies, and they retired to the shel- 

 ter of the banks. But occasionally, with the advent of 

 milder days, they would issue from the shelter of the 



269 



