Hostility, active and passive 170 
Hypermetamorphosis, in bees 166 
Ichneumonid parasites of bees 158 
Inquilines of bees 153 
Kumlien, L., article by 1 
Lasiurus borealis 181 
Leaf -cutter bees 160 
Loxotropa modesta 188 
Lyon, on bats 181 
Megachile addenda 160, 161 
Megachile infragilis 158, 159 
Megachile latimanus 162 
Megachile melanophwa 162 
Megachile, nesting habits 162 
Melissodes trinodis 164 
Mutations 175 
Nomada imbricata 153 
Momada pulchella 153 
Oecological features of evolution 169 
Oenothera lamarckiana 177 
Osborn, H. F., quoted 164 
Osmia atriventris 158, 159 
Osmia leucomelama 154 
Parasitic bees, behavior 155 
Potamogeton pectinuatus, as duck food 168 
Proceedings 145 
Prosopis pygmwa 159 
Eed Bat, number of young 181 
Sheldon, on red bat 181 
Sierolomorpha 186 
Skavlem, H. L., article by 168 
Stelis minuta 154 
Stelis nasuta 153 
Stelis sexmaculata 155, 156, 159 
Time as a factor in evolution 171 
Triepeolus helianthi 164 
Vallisneria spiralis 168 
Ward, H. L., article by 181 
Wild celery, as duck food 168 
Wisconsin birds 1 
(See also, special index, on page 140.) 
