INDEX. 



321 



Pneumodermon, 252. 

 Podophrya, 51, 157, 174, 237. 



development of, 286. 

 Polarity in animals, 127. 

 Poles of the egg, 83, 35. 

 Polycystinae, 49. 

 Polymerous, dorso - ventrally, the Zo- 



ophyta, 195. 

 uro-cephally, the Articulata, 



195. 



Polypi, development of, 289. 

 anatomy of, 57, 177. 

 Pore, abdominal, 228. 

 Primarily created animals, condition of, 



105. 



Primitive stripe, 305. 

 Primordial state of the first created ani- 

 mals, 105. 



Privet Hawk-Moth, 222. 

 Progressive steps, animals related by, 265. 

 Property, scientific, note on, 37, 304. 

 Prostomum, 35. 

 Protean animalcule, 9. 

 Protococcus, 133, 136. 

 Protozoa, 160. 



and Articulata, relations of, 244. 

 Zoophyta, relations of, 237. 

 Mollusca, relations of, 243. 

 bilaterality of, 175. 

 development of, 285. 

 progressive development of, 40. 

 self-division of, 61. 

 Protula, 251. 

 Pseudopodia, 12, 44. 



rapid movement of, 13. 

 Psolus, 192. 

 Pterodactylus, 278. 

 Purkinjean vesicle, 32. 



Q- 



Quatrefages on Amphioxus, 228. 

 K. 



Radiata, bilatorality in, 128. 



Rank, relative, of Articulata, 124, 214. 



Mollusca, 124, 214. 

 Red-snow plant, 135. 

 Reduction of repeated parts in Articulata, 



215. 



Zoophyta, 

 187, 192. 

 Relation of organs in typical forms, 126, 



159. 

 Reproduction by budding, law of, 109. 



of lost parts in animals, 94. 

 relation of, to form, 265. 

 bilaterality, 



266. 



Reptilian fishes, 263. 

 Respiratory branches, 190. 

 Rhizogeton, 73, 242. 

 Rhizopoda, 14. 



Riirhtancl left in animals, 127. 



Kotalia, 14. 



Rotiiera, 275. 



Round- worm, formation of egg in, 36. 



S. 



Sagitta, 96. 



Saltatory cilia of Infusoria, 150. 

 Sand-eel, 227. 

 Saprolegna, 133, 141. 

 Sarcode, 11. 



Scientific property, note on, 37, 304. 

 Scorpions, 220. 

 Scyphostoma of Aurelia, 67. 

 tentacles of, 242. 

 organization of, 241. 

 Sea-anemone, 57, 177. 



young of, 177. 

 development of, 289. 

 Secondary causes, Owen on, 102. 



relation of embryo to, 



111. 

 prevalence of, a matter 



of degree, 112. 

 Seeds floating in the air, 29. 

 Segmentation of the egg, 284. 

 Self-division among Corals, 61. 



Protozoa, 61. 

 Vertebrates, 85. 

 in Tape-worms, 82. 

 of Myrianida, 80. 

 worms, 80. 

 Sea-anemone, 61. 

 Shell, relative position of, in Cephalopoda, 



212. 



Shrimps, 274. 

 Siamese twins, 86. 



Similarity of all animals at earliest pe- 

 riod of growth, 111. 

 Siphonactinia, 180. 

 Siphydora, 41. 

 Sipunculacea, 250. 

 Siren, 2G3. 

 Snail, 203. 



development of, 294. 

 Snapping turtle, 304. 

 Song-sparrows, 277. 

 Species, affinities among, 276. 

 Sphinx, 223. 

 Spiders, 220. 

 Spinal column, rudiment of, 229. 



nature of, 23.1. 

 Spinal cord, double, 127. 

 Spiracles, 224. 



Spiral type of animals, 160, 175. 

 Spirillum, 23. 

 Spirostomum, egg of, 31. 

 Sponge, 40, 156. 

 Spontaneous generation, 15. 



origin of theory, 



28. 



probability of, 

 106. 



