Part 86

South Africa, insects, 128

South Carolina, natural oyster grounds, 111

Sow bug, eyes, 110

Space, perception by tortoises, 121

Sparrow, field, 117 fox, 117 song, 117 tree, 117 vesper, 117 white-crowned, 117 white-throated, 117

Spawning habits of fish, 112

Specimens, collecting natural history, 63 collection, 49, 50 determination, 49, 51 determined, 52 numbering, 50, 51 preservation, 49, 50

Spiders, cocooning habits, 118 collecting, 58 habitats, 125, 138 habits, 117 instincts, 117 mating habits, 115 mental powers, 117 Nearctic, 72 systematic literature, 71

Sponges, behavior, 116 reactions, 116

Squirrels, behavior, 121 habits, 115

Stable plant formations, 88

Starfish, behavior, 105 locomotion, 110 natural history, 115

Status, dynamic, 29, 31

Stimulations, responses to chemical, 97

Stimuli, influence upon growth, 95 influence upon protoplasm, 95 similar effects of diverse, 98

Stones, fauna under, 144

Stratigraphy, relation of marine bionomy to, 22

Stream, animals of a small, 147, 148 environment, references to, 113 fish, ecological succession, 133 fish of a small, 147 habitat, 147, 148 Isopods, 106

Stress, condition, 30, 31

Struggle among organisms, 123

Struggle for existence, 2, 122, 123 in a lake, 123 in Guiana forests, 124 in the sea, 123 references, 126

Studies, quantitative, 61

Style brief, Wistar Institute, 68

Style manual, 68

Subterranean. See also Cave

Subterranean animals, 58, 86, 143, 144, 145

Subterranean Isopods, behavior, 108

Succession, animals in oyster beds, 131 associations of inland habitats, 91