INDEX OF SUBJECTS 



351 



Radiolaria, numerous groups 

 persistent from Primary 

 times to the present, 194 

 Radiolitae, 216 

 Raniformes (frogs, etc.), 80 

 Reduction of limbs, 209 

 Regression, phenomena of, 217 

 Regulus cristatus, 136 



ignicapillus, 1 36 

 Renaissance, naturalist philo- 

 sophers of, 24 



Reptiles, Arch&opteryx, link 

 between Birds and, 74, 113, 

 249 



Cretaceous, 9, 301 



Darwin on, 41 



Gaudry on their evolution, 



99 



Jurassic, 9, etc. 



Lamarck on origin, 31 



Marine of Secondary seas, 

 170, etc. 



Permian, 248, 299 



possible origin in Carboni- 

 ferous times, 252 



predominant in Secondary 

 times, 245 



Triassic, 297, 299 

 Requienia, 165, 216 

 Rhabdoceras, 214 

 Rhinoceros, Cuvier on, 13 



Gaudry on evolution of , 1 5 1 -3 



of Java, discovery, 8 

 Rhinoceros antiquitatis , 236 



etmscus, 152 



pachygnathus, 152 



Ronzotherium (first), 312 



Schleiermacheri, 152 



tichorhinus, 152 

 Rhizopoda, Haeckel on, 45 

 Rynchocephalians (ancestors of 



the Sphenodon), 171, 210 

 Rynchonellae, 159 

 Rhytidostens, 303 

 Rodents, Haeckel on, 54 

 Rosa's law, 239 

 Rotalia, 163 

 Roussettes (Cheiroptera like 



squirrel), 315 



Rudimentary organs, bearing 

 on transformist hypothesis, 

 218 



Rudistae, 102, 165-6, 216 



SACK-WORM stage of Haeckel, 



55 



Salamander, 4, 56 

 Saltation, hypothesis of abrupt 



variation of species, 34, 267, 



273, 277 



Sarigues, the, 56, 172 

 Sauravus, 248 

 Saurians, Lamarck on, 31 

 Scaphites, 196, 286 

 Scelidosawidce , 299 

 Schizotherium, 153 

 Schloenbachia inftata, 211 

 Schlotheimia, 260 

 Scolecide stage of Haeckel, 5 5 

 Scolopendra, 31 

 Scorpionidae go back to Silurian 



period, 50 

 Selachians, carnivorous fishes 



very common in Primary 



times, 51 



Silurian forms, 321 

 Selection, Darwin on natural, 



25, 35 et seq. 

 Semnopitheci, 56 

 Sepias, 48 

 Sharks, ancestors of, 169 



Eocene and Pliocene, 197 

 Shells, Ammonites, 257-61 



Coutagne on Helices (snails), 

 129 



Hyatt on Nautilidce, 240 



Lingula, unchanged from 

 Cambrian times to the pre- 

 sent, 326 



of Helix, 132 



uncoiling of Cephalopods, 

 228 



varieties in Bulimus, 131 

 Siberia, great quadrupeds pre- 

 served in its icefields, 10 



Sicily, dwarf elephants of, 



204 

 Silesitce, 286 



