174 



INDEX 



Sea anemone, behavior modifiable, 



105 



Sea beach, associational study, 136 

 Sea-bottom, 



animal life, 63, 136 



fauna and flora, 64 



quantitative study of animals, 63 

 Sea, 



conditions of life in, 134 



conditions of production in, 87 



cycle of matter in, 87 



metabolism in, 87 



struggle for existence in, 123 



valuation of the, 136 

 Seashore, 



animal ecology, 63, 64 



animals, 146 



Season, influence on digestion of 

 cold-blooded vertebrates, 100 

 Seasonal succession, 



animals, 140 



beetles, 140 



butterflies, 140 



Hemiptera, 141 



in old forest ponds, 140 



plants, 140 

 Sea-urchin, 99 



resistance to lack of oxygen, 99 



resistance to potassium cyanide, 



99 

 Sebago salmon, internal parasites, 



129 



Second-hand books, dealers in, 65 

 Sense organ, 



Arthropods, effect of caves on, 

 101 



offish, 113 

 Senses of insects, 111 

 Sensory adaptations of cave-inhabit- 

 ing bats, 112 

 Sensory reactions of Amphioxus, 



116 



Sequence of changes in environ- 

 ment, 104 



Sessile habit, influence, 100 

 Serpents, 



food, 129 



Pennsylvania, 129 

 Sexual characters of Araneads, 

 secondary, 115 



Shawnee Cave plankton, ecological 



study, 145 

 Shell-fish, 



ciliary action, 114 



feeding reflexes, 114 



food, 114 



function of mucus, 1 14 

 Shell-fish industries, 



biology, 114 



culture, 114 



utilization, 114 



Shell-fisheries of Massachusetts, 108 

 Shore, animal ecology of the, 139 

 Shore animals, associational study, 



139 



Significance of courtship of Ara- 

 neads, 115 

 Skokie Marsh area, ecology of 



mollusca, 137 

 Slaves of ants, 120 

 Slug, 



eyes, 110 



feeding habits, 125 

 Snail, 



eyes, 110 



mud, 111 



pond, 120 

 Snails, 



and plants, 125 



feeding habits, 125 



food, 125 



in grave, 144 



influence of environment on, 100 

 Snout-beetles, 76 

 Snowbird, 117 

 Social community, 18, 123 



animals, 131 



insects, 135 



interrelations, 131 



oyster bank, 132 



sea-bottom, 136 

 Social control, by voices among 



pigeons, 106, 134 

 Social life, 



from comparative and phylo- 

 genetic standpoint, 132 



insects, 111 



multiple origin, 132 



origin, 132 

 Social parasitism, 126 



