362 



ANIMAL COMMUNITIES 



Water-striders, scientific names: 

 Gerridae, 185. 

 Gerris: 



marginatus, 155. 

 rufoscutellatus, 155. 

 Mesovelia bisignata, 155. 

 Rhagovelia cottar is, 98, 117. 

 Weasel, 201. 

 Weeds, avoided by aquatic animals 



during flood, 105. 

 Weevils, 167. 



Wheel animalcules. See Rotifers. 

 Whitefish: 76, 77, 82, 85; blackfin, 81, 



82; Hoy's, 81, 82, 85; long-jaw, 79, 



80, 82, 85. 



Willow blossoms, visited by pollen- 

 gathering insects, 224-25. 

 Willow sawfly: large, 267; spotted, 267. 

 Wildcat, 242. 

 Wilting coefficient of soil, 158. 



Wind : influence on circulation in lakes, 

 61; relation to light penetration, 63, 

 to evaporation, 160, 162, 163. 



Wolf, 15, 167, 201, 236, 238, 245. 



Wood pewee, 196, 244. 



Wood thrush, 241. 



Woodchuck, 215, 233, 236. 



Woodcock, 189, 191. 



Wood-frog, 244. 



Woodpeckers: 196, 274; downy, 229; 

 in beach drift, 219; red-headed, 242. 



Worms: flat, 20; round, 20. 



Wren: long-billed marsh, 171; short- 

 billed marsh, 181. 



Yellowlegs, 181. 



Yellowthroat, northern, 189, 262, 275. 



Zonation in forest edge, 263. 



