Part 83

Reproduction, fresh-water mussels, 114, 115 physiology, 100

Reptiles, Arizona, 148 associations of desert species, 148 collecting, 58 desert species, 148 food of desert species, 148 New Mexico, 148

Research methods, in plant ecology, 59, 88

Research, processes, 55 speculative method in, 55

Respiration, of an inland lake, 87 protoplasmic, 97

Response, bird migration as a, 109 to strain, 85

Responses, Isopods of ponds and streams, 106 study, 15 to chemical stimulations, 97

Rheotaxis in Isopoda, 106

Rheotropism in fish, 115

Rhynchophora, biologies, 76 food habits, 72 parasites, 76

Ring-dove, blond, 110

River entomology, Illinois, 75

River fauna, Danube delta, 145 lower Elbe, 138

River habitat, flooded delta, 145

River plankton, Illinois, 147

Rocky Mountain locust, enemies, 77

Rodentia, 107

Rose coral, feeding reactions, 109

Running water, effect on productivity of fish, 101

Salamanders, habits, 119

Salmon, internal parasites of Sebago, 129

Salpa and evolution of life, 123

Salt-marsh Amphipod, habits and life history, 119

Salt-water fauna, 111. See also Marine animals

San Diego region, Chætognatha of, 115

Sand, ants, 149 areas of Illinois, biology, 146 prairies of Illinois, associational study, 139

Sandy flats of the sea coast as a biotic association, 136, 137

Sarcophagidæ, relation to lake beach débris, 147