THE PRAIRIES 325 



their haunts. The Blue-winged Teal and Wilson's Phala- 

 rope nesting in the long grasses on the border of the slough, 

 fluttered from their eggs only when one seemed about to 

 step upon them, but the Terns sprang into the air and, with 

 sharp screams, came to meet me when I was thirty yards 

 away. 



On June 25, there occurred an unusually heavy fall of 

 rain, raising the water in the slough several inches and 

 threatening to inundate the little island. But the Terns 

 saved their eggs from the flood by bringing fresh nesting 

 material and raising the height of their home ; though, 

 whether the action was performed with a definite object or 

 was merely such a display of nest-building instinct as is not 

 infrequently seen during incubation, it is difficult to de- 

 termine. 



On July 5, after an incubation period, therefore, of sev- 

 enteen days, the first egg was hatched. Three days later, 

 with Ernest Seton, who had joined us on the 3d, I visited 

 the nest, expecting to see a pair of downy young but, to our 

 surprise and disappointment, it was deserted. Evidently, 

 however, there was something not far away in which the 

 Terns were greatly concerned. With piercing screams they 

 darted at us, once actually hitting Seton 's hat. 



Search failing to reveal any sign of the young birds, the 

 camera was left to play detective. Focusing it on the empty 

 nest and surrounding it with cat-tails, we attached some 

 seventy feet of tubing and retired to the high grasses of a 

 neighboring dry bank. But we were not hidden from the 

 Tern. She hovered over us, shrieking her disgust with 

 scarcely a pause, turning her long beak to this side and that, 

 as she brought each eye in turn to bear. Finally her craiks 

 grew softer, and, fluttering over the nest, she uttered a soft 

 u'heent-ivJieent-wlteent, which probably meant to her chicks 

 " It 's all right ; come back home now. ' ' After half a minute 

 of this calling, she fluttered lower and dropped out of sight 

 behind the reed barriers. 



