INDEX 



IIII 



Vegetation, Larger (Higher), Fresh- Water, 



178-209; cycle of matter, 207, evolution, 



198, references, 209, zones, 196; see Plants, 



aquatic 

 Veliidae. 933 

 Venation, wing, 916; of stoneflies, 916; see 



Insecta 

 Vertebrata, 1021-1066; adaptations, 1022, 



references, 1066; see Amphibia (Batrachia); 



Birds; Fishes; Mammals; Reptiles 

 Viviparidae, 987 

 Viviparus, 987; interlextus, 987 

 Volvocaceae, 143 

 Volvox, 146, 269; aureus, 269, globalor, 269, 



perglobator, 269, spermatosphara, 269 

 Vortex, 340 



Vortex (?) cavicolens, 361, 363 

 Vorticella, 293; campanula, 293 



Wardius, 386; zibelhicus, 386 



Water; acid or alkaline characteristics of, 40, 

 ammonia in, 39, bacteria found in natural, 

 96, number in, 96, 1070, biological con- 

 ditions in, 46, carbon dioxide in, 39, 

 chemical factors, 36, circulation, 27, in 

 lakes, 27, conveyor of disease, 1068, current 

 strength in streams, 23, daily depth migra- 

 tions, 32, 43, density, 22, distribution of 

 gases, 37, of life, 35, expansion in freezing, 



21, gases dissolved in, 36, general solvent, 



22, identification of soiurce of, 1080, index 

 of suitability, 46, influence of currents in, 

 28, odors in, 1071, 1072, oxygen content, 

 37, penetration of light, 29, 30, physical 

 conditions of, 22, physical environment of 

 organisms in, 9, pressure in, 34, quantity 

 of life in, 46, of plankton in, 47, 48, reser- 

 voirs, purification of, 1074, 1076, 1077, 

 rhythms of organisms, 43, seasonal changes, 

 2,3, solubility of gases in, 37, tastes in, 1071, 

 temperature, 32, in streams, 32, terriginous 

 bottom, 45, thermal properties, 21, tur- 

 bidity, 29, 36 



Water Biology, Fresh-; see Biology, Fresh- 

 Water 

 "Water-bloom,"' 100 

 Water bodies, physical features of, 8 

 Water bottle, 80 



Water glass, 87 



Water Life, Fresh-; see Biology, Fresh-Water 

 Water organisms, physical environment of, 9 

 Water plants and vegetation; see Plants. 



aquatic; Vegetation, aquatic 

 Water supplies, tastes and odors in, 107 1 

 Water systems, organisms in pipes of, 1081 

 Waters, flowing, 2 

 Waves and their action, 28 

 Wheel animalcules; see Rotatoria 

 WhirUgig beetles, 906; see Coleoptera; Insecta 

 Wilsonema, 495 

 Wing venation, 916 

 Winter buds (hibernacula), 192 

 Wlassicsia, 711; kinistinensis, 711 

 WoUea, no; saccata, no 

 Worms, earth; see Chaetopoda; Oligochaeta 

 Worms, free-living; see Nematoda; Nemer- 



tina (Nemerteans) ; Turbellaria 

 Worms, parasitic; see Acanthocephala; Ces- 



toda; Gordiacea; Nematoda, Parasitic; 



Parasitic Worms; Trematoda 

 Wyeomyia (larva), 944 



Xanthidium, 141; Jasciculatum, 141 

 Xiphidiocercariae, 416 

 Xystonotus, 865: asper, 865 



Zannichellia, 189; repens, 183, palustris, 19c 



Zeugorchis, 407; aequaius, 407 



Zoethamnium, 294; adamsi, 294 



Zone, shore, 3 



Zones of vegetation, 196; characetum, 196. 

 nupharetum, 196, phragmitetum, 196 

 potamogetonetimi, 196, scirpetum, 196 



Zoochlorella, 153 



Zooecium, 948 



Zoophytes, 301 



Zoosporangium, 119 



Zoospores, 118 



Zostera nana, 185 



Zygnema, 142 



Zygnemaceae, 141 



Zygnemeae, 142 



Zygocotyle, 388; ceratosa, 388 



Zygocotylinae, 388 



Zygoptera (imago), 922, (nymph), 928 



Zygospore, 119 



