334 



Index. 



Paradise birds, 201 



Parallel or analogous variation, 



302 



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 

 Psyche, 61 

 Pteromalus, 65 



Reciprocal 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 

 Revision, 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 



Rotifera, 66, 171 

 Ruminants, 206 



Saltatory evolution, 83, 157, 296 

 Salter on variation of straw- 

 berry, 91 

 Saphirrina, 176 

 Sassafras in Europe, 90 

 Scalpellum, 181 

 Schaff er on parthenogenesis, 56 

 Sea-gull, 92 

 Sea urchin, 66 

 Secondary sexual characters, 



166 



Semper on Lymnaeus, 92 

 Sex of parent, influence of, 18, 



123 

 Sexual differences in 



Agrion, 239 



Alcippe, 183 



anchorella, 179 



argonauta, 237 



arthropoda, 173 



barnacles, 179, 181 



beetles, 191 



branchippus, 173 



call duck, 236 



cave beetles, 237 



cicada, 188 



cladocera, 175 



copepoda, 175, 177 



crabs, 186 



crayfish, 188 



cryptophyalus, 183 



cyclops, 175 



gelassimus, 189 



ibla, 182 



insects, 188, 236 



lernentoma, 176 



locustidae, 188 



