424 



Mole, 367 



Australian, 322 

 Mollusca, 72 

 Molluscoida, 48 

 Molting of crayfish. 98 

 Monarch butterfly, 172 

 Mongoose, 365 

 Monitors, 248 

 Monkeys of America, 373 



Old World, 375 



orang-utan, 376 



Saki, 374 



spider, 374 



squirrel, 374 

 Monobia quadridens, 181 

 Monotremata, 319 

 Moose, 342 

 Morula, 385 

 Mosquitoes, 156 

 Moths, 162 



carpenter, 164 



coccid-eating, 164 



codling, 164 



gypsy, 169 



hawk, 170 



meal, 164 



owlet, 166 



tussock, 168 

 Mud-eel, 229 



Multiplication, sexual, asexual, 11 

 Murida;, 352 

 Musca domestica, 154 

 Muscardinius avellanarius, 353 

 Muscidse, 154 

 Mus decumamis, 352 



minutus, 352 



musculus, 352 

 Muskrat, 352 

 Mustelida>, 359 

 Mutation, 390 

 Mya arenaria, SO 

 Mydaus milictes, 360 

 Mygale, 106 

 Myogale moscata, 367 

 Myriapoda, 111 

 Myrmecophaga jubata, 324 

 Myrmecophagida?, 324 

 Myrmicida", 180 

 Mytilus, 74 



Nasalis, 375 

 Natica, 83 



Natural selection, 388 

 Nauplius, 90 



Nautilus, 86 

 Nebalia, 93 

 Necrophorus, 150 

 Necturus, 223, 231 

 Nemathelminthes, 41 

 Nematocysts, 19 

 Nematoda, 41 

 Nematus ribesii, 175 

 Nemertinea, 39 

 Neotony, 232 

 Nephridia, 68, 201 

 Nereis, 69 

 Newts, 232 



Nictitating membrane, 271 

 Night hawk, 300 

 Noctuida;, 166 

 Non-ruminants, 334 

 Notolrema marsupiatum, 226 

 Nucleoli, 383 

 Nucleus, 2 

 Nudibranchs, 83 

 Nuthatches, 305 



Ocelli, 123 

 Ocneria dispar, 169 

 Octocoralla, 31 

 Octopus, 85 



Odocoileus virginianus, 339 

 Odonata, 129 

 Odontoglossa>, 286 

 Odor of bugs, 141 

 CEstridffi, 156 

 Oligocottue snyderi, 198 

 Omasum, 337 

 Ophidia, 239 

 Ophiopholis, 58 

 Ophiuroidea, 56 

 Orb weavers, 107 

 Orientation, 7 

 Ornithorynchus, 320 

 Orthogenesis, 390 

 Orthoptera, 132 

 Osculum, 10 

 Ostracoda, 90 

 Ostrea, 74 



edulis, 77 



virginiana, 77 

 Ostrich, 278, 279 

 Otaria jubata, 365 



ursina, 365 

 OtoHth, 203 

 Otter, 359 

 Ova, 384 



size of, 384 



