Part 88

Trapping, 39, 60

Tree frogs, behavior, 112 color changes, 112

Trees, insects affecting, 74

Trematoda and trematode diseases, index to literature, 129

Trial and error, 104

Tubicolous Annelids, behavior, 112

Turbellarian, behavior, 127 ecology, 127 food, 127 habitat, 127

Turtles, cultivation, 110 discriminative ability of painted, 109 food, 129 formation of habits, 105 natural history, 110 Pennsylvania, 129

Turtur risorius, 110

Types of eyes, image-forming powers of various, 110

Typography, 68

Use of theory, 40

Utah, 55

Vanessa antiopa Linn., phototropism, 116

Variation, in animals, 96 in plants, 96 statistical, 60

Vegetation, and animal associations, 90 and control of land animal communities, 133 Caithness, 88 changes in, 88 controlling land animal communities, 90 correlated with lake fauna, 140 development and structure, 88 invading alluvial flats, 89 invading new land surface, 89

Vegetational change, influence upon animals, 85

Vegetational control, of relative evaporating power of the air, 90 of relative humidity of air, 90

Vegetative cycles, causes, 88

Venus mercenaria, growth, 108, 114 habits, 114 life history, 108

Veterinary zoölogy, bibliography, 129

Vineyard Sound, invertebrate animals of, 136

Visual discrimination in raccoons, 110

Vital conditions, optimum, 99

Vital optimum, 94

Voices of pigeons as means of social control, 106, 134

Volcanic activity and new land surface, 89

Volcanic islands, new flora, 89