INDEX. 



Mark of age, fossils, 83. 



"Mark or seal" of living types, 



Forbes, 124. 



Marks of an organism, 175. 

 Matter and form of individual, 160; 



properties of, not evolved, 374. 

 Mature individuals used, 209. 

 Maximum thickness of rocks, 59. 

 Medial order, 18. 

 Medium, as environment, 113. 

 Mesocambrian, 52. 

 Mesoderm, 173. 

 Mesosaurus tumidus, 362. 

 Mesozoic, 22, 23, 26. 

 Metabolic changes, 117. 

 Metameric type in classification, 236. 

 Metameres, 222, 224. 

 Metazoa, characters of, 225. 

 Metazoan, a tissue-bearing animal, 



173- 

 Migration and modification, 140; of 



species, 123. 

 Mineral character not sign of age, 



77- 



Miocene, 21. 



Mississippi River, and time, 57. 

 Mode of curvature of nautiloid shell, 



339- 



Modifications of brachidium, 277; of 

 specific characters, 125; of sut- 

 ures, 354. 



Molecule, and cell, 166. 



Mollusca, according to Lankester, 

 246; branch, and classes of, 246; 

 definition of, 204; described, 244; 

 245 ; digestive system of, 247 ; 

 and evolutional history, 239; gen- 

 eral character of, 242 ; muscular, 

 nervous, and motory systems of, 

 247; Zittel's classification, 239. 



Molluscan type of structure, 225. 



Molluscoidea, definitions of, 204 ; 

 described, 244. 



Monomeric and dimeric types, 235; 



Morphephebic stage, 94. 



Morphological characters and an- 

 cestry, in; and time, in; differ- 

 entiation (evolution), 89 ; and 

 physiological characters, 176; unit, 

 the cell, 164. 



Morula, 172. 



Motor organs, differentiation of, 228, 

 232. 



Multiplication of parts before spec- 

 ialization, 229. 



Murchison, 22, 23, 28. 



Murchison's term system, 71. 



Muscular motion, meaning of, 228, 

 230; and skeletal organs, 232. 



Mutability, example of, 187; a fun- 

 damental law, 296; a law of evo- 



lution, 162 ; law of, expressed by 

 symbols, 187 ; and immutability, 

 125 ; and origin of species, 126, 

 154, 187; and phylogeny, 294; 

 of species, 125, 126, 151, 155; of 

 species and evolution, 151; tenet 

 of, 155- 



Mutable species, temporary, 154. 



Mutable, what is? 187. 



Mutations, 207; and variations, 70. 



Narrowing the limit of variability,. 

 322. 



Natural-history classification, 115, 

 200. 



Natural-history provinces, 113, 122; 

 of Woodward, 115; of Sclater, 115; 

 of Wallace, 115; Fischer, 115. 



Natural law of succession, in. 



Natural selection, 156, 179; in Dar- 

 win's theory, 194; and geological 

 evidence, 367; and living organ- 

 isms, 366. 



Natural variation, 296. 



Nature of species, new conception 

 of, 156. 



Neanic, 94. 



Nekton, 116. 



Neocambrian, 52. 



Neocene, 30. 



Neozoic, 22. 



Neritic plankton, 116. 



Nervous system and locomotion, 231. 



Neues Floetzgebirge, 13, 1 6. 



New species, characters of, not all 

 new, 191; idea of, 189; New York 

 geologists, 25; rocks, Amos Eaton, 

 19. 



Niagara gorge, cutting of, 56. 



No evidence of evolution of classes, 

 241. 



Nomenclature of geological con- 

 gress, 69; of provinces, 115. 



Normal growth, 179; habitat, 115. 



Nullipore zone, and Ctenobranchina, 

 137- 



Numbers of genera, and systems, 86, 



Numbers of genera of Zoantheria, 

 84. 



Old and new schools of opinion, 121. 



Olenellus fauna, 52. 



Ontogenesis and change of function, 

 95; and phylogenesis contrasted, 

 95, 178; a repetition of phenomena, 

 95; results of, 176; and stages of 

 growth, 94. 



Ontogenetic growth of sutures, 352. 



Ontogeny and Ontogenesis, 180; and 

 Phylogeny, 158. 



Oolitic group, 18. 



