394 



INDEX. 



Species, successive and develop- 

 mental stages of, 95 ; closely ad- 

 justed to environment, 143; defi- 

 nitions of, Buffon, 150; Cuvier, 150; 

 De Candolle, 150; Haeckel, 162; 

 Huxley, 154, 184 ; Lamarck, 152; 

 Linne, 150 ; Pritchard's, 297; Os- 

 car Schmidt, 162; Tournefort, 150; 

 Zittel, 150. 



Species, Forbes' ideas about, 123. 



Species and genera, importance of, 

 205; and genus of Aristotle. 200; 

 as immutable, 153; importance of, 

 149, 162; initiation of, 322; number 

 of, 149; of the paleontologist, 207; 

 temporary continuance of, 28. 



.Specific centres of Forbes, 114, 122; 

 Darwin's view of, 123; of distri- 

 bution, 114; characters, modifica- 

 tion of, 125; evolution, 253; and 

 generic names, uniform usage 

 202; variability, 299. 



Spirifer, 285; the genus analyzed 

 by Hall, 312. 



Spiriferidte, 279. 



Spirifer striatus and mutability, 188. 



Spirifers, evolution of appendages, 

 302; of delthyrium, 304; deltid- 

 ium, 304; hinge area, 305; median 

 fold and sinus, 308 ; median septum, 

 310; shell proportions, 302; pli- 

 cation surface, 308; structure of 

 shell, 310; surface-markings, 307; 

 surface spines, 310. 



Spontaneous generation, 154. 



Stage, the term in Geology, 69. 



Stages of development, 171; of 

 growth in ontogenesis, 94; of in- 

 dividual growth, 94. 



Standard classification, 203; periods, 

 52; time-scale, 54; units of time- 

 scale, 31. 



Steps of progress in development, 

 167. 



Stony corals, 84. 



Strata in classifying rocks, 65; as 

 data of the formation scale, 66; 

 parts of a formation, 67. 



Stratified rocks, classification of, 65; 

 and geographical conditions, 71; 

 and geological time, 65, 



Stratigraphical division planes, 29; 

 order and locality, 73. 



Stratum, or groups of strata, 69. 



Strombidtz and Chenopodidce, 143. 



Structure and environment, 147. 



Struggle for existence, in Darwin's 

 theory, 194; wanting in embryo 

 stage, 173. 



Succession and adjustment of spe- 

 cies, 117; of species and stages of 



development, 95; of suture char- 

 acters, 353. 



Supercretaceous group, 18. 



Superior order in geology, 18. 



Supermedial order in geology, 18. 



Superposition of rocks, 77. 



Survey, U. S. Geological, 30. 



Sustentation, the functions of, 177. 



Sutures of Ammonoidea explained, 

 350; Ammonitic type, 352; Cera- 

 titic, Helictitic, and Medlicottian, 

 351; classification, 350; Goniatitic 

 type, 351; Nautilian type, 350; 

 Pinacoceran type, 352. 



Synthetic method in classification, 

 238; types, mesozoic vertebrates, 

 361. 



System in Geology, 69; Cambrian, 

 31; Carboniferous, 34: Cretaceous, 

 36; determining age of, 37; De- 

 vonian, 33; and era, 71; Juras- 

 sic, 36; Murchison's term, 71; Or- 

 dovician, 32; Quaternary, 37; Si- 

 lurian, 33; Tertiary, 37; Triassic, 

 35- 



Systematic classification, 10. 



Systems of classification, 27, 206; 

 geological, 31; not world-wide, 

 29; and revolutions, 39. 



Taconic revolution, 41. 



Tait, time estimate, 57. 



Taxonomic rank and adaptation. 

 142; and environment, 148; and 

 geological range, 92. 



Teeth of mammals, Osborne, 363. 



Teleology, in Biology, 378; and the 

 organism, 163. 



Telotremata, evolution of, 256. 



Temperature as environment, 113. 



Temporary continuance of species, 

 28; nature of species, 154. 



Tentacles, meaning of, 228. 



Terebratulina septentrionalis, char- 

 acters of, 258. 



Terms of classification, genus. 201; 

 species, 201 \ genus ,proximum, 201; 

 medium, 201; summum, 201; ordo, 

 order, 201; classis, class, 201; indi- 

 vidual. 201 \ embranchment, branch, 

 201; subkingdom, 201; phyllum, 

 201; type, 201. 



Terrestrial province, 113. 



Tertiary of Cuvier and Brongniart, 

 12. 



Tertiary period in geology, 24; sub- 

 divisions of, 26. 



Tetracoralla, rate of differentiation 

 of, 85. 



Tidal friction, time estimates, 56. 



Time in cutting Columbia gorge, 56; 



