INDEX. 



393 



Protoplasm, defined by Huxley, 164. 



Protozoa, definition of, 203; develop- 

 ment of, 165. 



Protozoa and metazoa, growth of, 

 167. 



Protozoan, a cellular animal, 173, 



Protozoic, 22, 23. 



Protremata, evolution of, 256. 



Provinces in natural history, 70, 113; 

 classification of, 115; and faunas, 



US- 



Provisional units of time-scale, 63. 



Psychozoic time, 24. 



Ptychopteria, initiation of species of, 

 322. 



Purposeful development of organ- 

 isms, 97. 



Quaternary of Reboul, 12. 



Quick evolution of Clymenidae, 349. 



Races in paleontology, 294. 



Radiate structure, 222. 



Rank and adaptation, 148; of ad- 

 justed characters, 139. 



Rank of characters, 192, 203 ; and 

 precision, 192; and antiquity, 192; 

 is it modified with descent? 196; 

 and their time values, 93 ; taxo- 

 nomic, and adaptation, 142 ; and 

 geological range, 92. 



Range and distribution of Strom- 

 bidae,i44; Chenopodidae, 144; Ceri- 

 thiidse, 145 ; Rissoidre, 145 ; geo- 

 logical, 70; geological and taxo- 

 nomic rank, 92. 



Rapid evolution of brachidium, 289; 

 of characters, 268 ; and natural 

 selection, 269; expansion at point 

 of origin, Hyatt's law, 341. 



Rate of accumulation of sediments, 

 5o,57; of denudation, 60, of differ- 

 entiation and new genera, 336 ; of 

 elaboration of characters of sut- 

 ure, 354; of erosion and geological 

 time, 57; of evolution, 262; of ex- 

 pansion of generic characters, 290; 

 of lowering of land surfaces, 60; 

 of removal of minerals from con- 

 tinent 59. 



Reality and mutability of species, 

 153; of specific centres, 122. 



Reboul, quarternary system, 12. 



Recapitulation theory, 158. 



Recurrence of characters, how ac- 

 counted for, 211. 



Red-sandstone group, 18. 



Region, 70. 



"Relationship of descent" of 

 Forbes, 124. 



Relative age, marked by fossils, 77. 



Relative order of deposits and de- 

 pression, 73 ; and elevation, 73 ; 

 thickness of deposits, 50. 



Removal of soluble minerals, Reade, 



59- 



Repetition of ancestral characters, 

 219 ; of characters, 259 ; of parts 

 and rank, 223. 



Representative species of Forbes, 

 115, 123; varieties, 207. 



Reproduction, 177, 193; of cell, 165. 



Restricted adaptation to zones, 140.. 



Restriction of variability, 299. 



Retardation, acceleration and, 197; 

 of development, 319. 



Retrosiphonata, 348. 



Revolution, Acadian, 42; Appalach- 

 ian, 34 ; and interruption of record, 

 46; palisade, 42; post-paleozoic, 34;. 

 Rocky Mountain, 43; Taconic, 41. 



Revolutions, geological, 39; as time- 

 breaks in history, 45. 



Rocks, chronology of, laws of, 76. 



Rocky Mountains, elevation of, 55;. 

 revolution, 43. 



Rostracea, evolution of, 256, 263. 



Scaliger's expansion of the genus r 



201. 



Schematic mollusk, Lankester, 325. 

 Schurman on antiquity of evolution,. 



153- 



Search for causes, 373. 

 Secondary, the term in geology, 12; 



period, 24. 

 Secretion, 177. 



Sediments, and Mississippi river, 57.. 

 Segmentation of ovum, 171 

 Selection of evidence, 365. 

 Senile, 94. 

 Septum, 91. 



Sequence of mineral deposits, 17. 

 Series, 69. 



Sex differentiation, 171. 

 Sexual selection, in Darwin's theory,. 



195- 



Silurian age, 25, 36; system, 71. 

 Similarity of form, and species, 162, 

 Sinking land and order of deposits, 



74- 



Skeletal and muscular organs, 232; 

 parts, 229. 



Smith, William, 21. 



Soft parts and hard parts, 98; of or- 

 ganism and ontogenesis, 98. 



Somites, 224. 



Sorting of materials, in sedimenta- 

 tion, 72. 



Source of sediments, 72. 



Specialization and differentiation,, 

 175; of fingers in reptiles, 362. 



