418 



INDEX. 



Parasites, notes on, by T, Spencer 

 Cobbold, 174. 



Pascoe, F. P., on new African GTenera 

 and Species of Curculionidie, 318. 



Penthelispa, 77 ; alternans, 1"28 ; crassi- 

 cornis, 129; nitidicollis, 129, 



Perignathio girdle of Echinoidea, by 

 Prof. P. M. Duncan, 179 ; termino- 

 logy of parts of perignathio girdle, 

 181. 



Peripatus, 167, 170 ; capensis, 170. 



Peristhenes adnotus, 319, 335, 33(). 



Peristoiuial region of ambulacra, 103. 



Philothermus, 59 ; depi'essus, 78. 



Phoca, brain of, 21. 



Phyllacanthus imperialis, 179, 186, 

 210. 



Phyllopoda, 294. 



Physiological Selection, an additional 

 suggestion on the Origin of Species, 

 Dr. Gt J. Eomanes on, 337 ; summary 

 and conclusion, 397. 



, or Segregation of the 



Fit, 350 ; argument from diver- 

 gence of character, 385 ; argument 

 from geographical distribution, 388; 

 argument from inutility of specific 

 differences, 382 , arguments on phy- 

 siological selection, 354, 365 ; argu- 

 ment from prevention of intercrossing, 

 378 ; argument from sterility between 

 species, 366 ; general summary and 

 conclusion, 397. 



Piazonias peregrinus, 318, 319 ; macer, 

 318, 320 ; velatus, 319. 



Pinnipedia, brain of, 21, 24. 



Platanista gangetica, 177. 



Platyomicus aridus, 326, 336; cordi- 

 pennis, 326 ; echinus, 326. 



Plotactis, 115, 116. 



Plumularia lagenifera, 157, 158, 161 ; 

 multinoda, 157, 161. 



PlumularidiB, 155. 



Pontocypris Davidsoni, 304 ; nitida, 

 303 ; trigonella, 304. 



Procyon, brain of, 10. 



Prolyctus bituberculatus, 128, 131. 



Proteles, brain of, 9, 10. 



Prototracheata, 167. 



Psalistus, 335. 



Psammechinus miliari.s, 179, 197, 211. 



Pseudotarphius, 58 ; Lewisii, 60, 63. 



Pycnomermi, 60. 



Pycnomerus, 59 ; alternans, 128, 131 ; 

 crassicornis, 129 ; distans, 129, 131 ; 

 nitidicollis, 129 ; sculpturatus, 60, 

 77 ; vilis, 60, 77. 



Races in regard to physiological selec- 

 tion, 358. 



Relations between survival of fittest and 

 segregation of fit, 395. 



Rhea, 174, 175. 



Rhizocephala, 262. 



Romanes, G. J., on Physiological Selec- 

 tion, 337-411. 



Sacculina, 261. 



Salmacis, 179, 187, 191, 192, 196 ; bi- 

 color, 179, 187, 210. 



Saphicus variegatus, 319, 336. 



Sargassum, 138, 139, 142, 159. 



Sclerostoma struthiouis, 263. 



Scobius, 326. 



Scolopendra, 167. 



Seals, brains of, 21, 23. 



Selaginopsis, 145. 



Sense-cells and ganglion-cells in Sphffi- 

 rotherium, 170. 



Sertularia, 138, 139; amplectens, 141, 

 142, 159; aperta, 138,150,159; bi 

 spinosa, 140; criuip, 139, 140, 159; 

 crinoidea, 141, 159; elougata, 140, 

 159 ; geminata, 143 ; humilis, 143 ; 

 megalocarpa, 142, 143, 159 ; minima, 

 138, 139, 159; operculata, 138, 148;. 

 imguiculata, 144; unilateralis, 139, 

 159. 



Sertularella, 133 ; capillaris, 133, 158 ; 

 crassipes, 133, 158 ; cuneata, 134, 

 158 ; diffusa, 136, 158 ; Johnsoni, 

 133 ; limbata, 134, 158 ; margari- 

 tacea, 133, 158 ; trimucronata, 135, 

 158 ; trochocarpa, 135, 158. 



Sharp, D., on Colydiidie from Ceylon, 

 lit ; on Oolydiidffi from Japan, 

 58. 



Siderodactylus delectans, 318, 320 ; 

 Oberthuerii, 318, 320 ; puellaris, 

 318, 320. 



Simondsia paradoxa, from Hog, 261. 



Sladen, W. P., and Prof. Duncan, on 

 test of ArbaciadiB, 2.5. 



Slavina and Ophidonais, by E. 0. 

 Boubfield, 264. 



, 264; appendiculata, 264, 268; 



lurida, 267, 268 ; serpentina, 267, 

 268. 



Species in regard to Physiological 

 Selection, 361. 



Sphadasmus, 335. 



Sphcerotherium, anatomy of, G. 0. 

 Bourne on, 161 ; copuiatory appen- 

 dages of, 164 ; stridulating organ of, 

 165, 172 ; tergites of body, 162 ; 

 trachea, primitive eharac. of, 167; 

 tracheal plates, 163. 



obtusum, 162, 164, 172, 173; 



retusum, 162, 164, 172, 173. 



Sphairularia, 261. 



