374 



(•1\'1C lUOLUGY 



Muskrat, 171 



Muskrat weed, 75 



Musquash root, 75 



Mussels, 273, 274, 279-281, 30() 



.Mustard, 70, 72 



Mutation, 338 



Myriapods, 317 



Myriophyllum, 307 



Mytilus, 276, 277. 278. 279 



Nagana, or tsetse-fly disease, 259 



Nam family, 345 



Nasturtium, 86 



Native plants, conservation of, 67 



Natural selection, law of. 335 



Nautilus, 274 



Nematodes, 264. 265, 266 



Nephritis, 232 



Nets, collecting, 11; fly, 119; ma- 

 terials for making, 12 



Neuroptera, 153 



Newts, 131, 314, 320 



Nicotine, 343 



Niggerhead, 280 



Nighthawk, 47 



Nightshade, 76 



Nitrates, 102 



Nitrifying bacteria, 222 



Nitrogen, 47, 98-101, 187 



Norman Percherons, 333 



Notebook, instructions for keeping, 

 in field and laboratory, 11 



Noxious mammals, 30. 44 : destruc- 

 tion of, 44 



Nuthatches, 51 



Nuts, importance of, and suggestions 

 for growing, 60 



Oak, 59, 83, 84 



Oats, 93 



Octopus, 274 



Oil, coal, 71 ; olive. 128 ; of tar. 128 



Onion maggot. 156 



( )phthalmia, 107 



Opium, 343 



Opsonic index, 248 



Orchard orioles, food of, 25 



Orchard pests, 155 



Oregon water hemlock. 76 



Oriental cockroach, 154 



Orioles, 48 



Orthoptera, 153 



Osprey, 45 



Otter, 171 



Ovenbird, 50 



Owls, 30, 34, 44 



Oxygen, 98, 194 



Oyster, 271, 274, 279; Atlantic, 273 : 



Pacific. 273 ; producing sickness. 



272 

 Oyster drill, 282 

 Oyster-shell scale, 156, 332 



Pacific clam, 278 



Pacific crab, 292 



Painted tortoise, 325 



Pangenesis, 338 



Panther, 169 



Parasites, use of. to control insects, 



161 

 Parasitic bacteria, 221 

 Parasitic protozoa, 255 

 Parasitic worms. 107 

 Parsnips, 105 

 Passenger pigeon, 36, 43, 44 ; egg 



of, 43 ; picture of, 36 

 Pasteur, 195, 209 

 Pavement ant, 155 

 Peach, 94, 165 

 Peach yellows, 214, 215 

 Peach-tree borer, 155 

 Pear, 94 



Pear and apple blight, 212, 213, 216 

 Pear slug, 157 

 Pear-blight beetle, 155 

 Pearl fishing, 279, 280 



