334 



Index. 



Paradise birds, 201 



Parallel or analogous variation, 



303 

 Parthenogenesis, 55 

 Peacock, variation in, 299 

 Perigenesis, 33 

 Pheasant, 203 

 Pigeon, direct modification of, 



94 

 " modification of male, 



218 

 Polar cells, 70 

 Polish fowl, 225 

 Pollicipes, 181 

 Psyclie, 61 

 Pteromalus, 65 



Peciprocal hybrids, 125 

 Reproduction, 19 



" by immature ani- 



mals, 43 

 " of bees, 9 



" of marine ani- 



mals, 9 

 " sexual and asex- 



ual, 11, 17, 249 

 Requisites of theory of hered- 

 ity, 16 

 Reversion, 17 



" by crossing, 132 



Darwin on, 10, 115 

 " in dogs, 10 

 " in horses, 10 

 " and Jager's hypothe- 

 sis, 44 

 " two kinds, 133 

 " in offspring of hy- 

 brids, 136 

 " of lost instincts, 135 

 Rhodites, 65 



Rolifera, 66, 171 

 Ruminants, 206 



Saltatory evolution, 83, 157, 296 

 Salter on variation of straw- 

 berry, 91 

 Saphirrina, 176 

 Sassafras in Europe, 90 

 Scalpellum, 181 

 Schafferon parthenogenesis, 56 

 Sea-gull, 92 

 Sea urchin, 66 

 Secondaiy sexual characters, 



166 

 Semper on Lymnaeus, 92 

 Sex of parent, influence of, 18, 



123 

 Sexual differences in 



Agrion, 239 



Alcippe, 183 



ancliorella, 179 



argonaut a, 237 



arthropoda, 173 



baruach's, 179, 181 



beetles, 191 



branchipiuis, 173 



call duck, 236 



cave beetles, 237 



cicada, 188 



cladocera, 175 



cope pod a, 175, 177 



crabs, 186 



crayfish, 188 



cryptophyalus, 183 



Cyclops, 175 



gelassimus, 189 



ibla, 182 



insects, 188, 236 



lernentoma, 176 



locustidae, 188 



