INDEX 385 



Mayow, and chemical physiology, 126. 



Mechanical work, done by the animal, 67 ; not done by the plant, 71. 



Mechanism, organic and inorganic, 78 ; 



the thermodynamic, 66 ; radical, 215 ; in life, 121. 



Membranes, semi-permeable, 95. 



Memory, 39 ; 



a possible cerebral mechanism of, 158 ; mechanistic hypotheses 

 impossible, 157. 



Mendelism, 196 ; 



a logical hypothesis, 199 ; terminology is a symbolism, 198 ; analogy of 

 unit characters with chemical radicles, 197 ; transmission of characters 

 of, 230. 



Mesoderm, 177 ; 

 origin of, 255. 



Metabolism, 37, 88, 209 ; 



analytic, 269 ; of animals, 65, 67 ; constructive, 269 ; destructive, 269 ; 

 direction of, 69 ; in green plant, 70, 75 ; intra-cellular, 99; integration 

 of its activities, 11 1 ; role of oxygen in, 105; specialisation of during 

 evolution, 305 ; synthetic, 269. 



Metaphysics of science, 45. 



Metazoan animals, 162. 



Mitosis, 182. 



Mobility, organic, 269 ; 



structural adaptations tending to, 275. 



Modifications of structure 



adaptive and non-adaptive, 251. 



Molecules, 353; 



size of, 116 ; in a gas, 115 ; aggregations of, 108. 



Molluscs, morphology of, 249. 



Morgan, and physico-chemical mechanisms, 128, 143. 



Morphogenesis, 257. 



Morphological evolution, tendencies of, 295. 



Morphological structures 



degeneration of, 251 ; suppression of, 250 ; coalescence of, 250 ; replace- 

 ment of, 250 ; specialisation of, 250 ; change of function of, 251. 



Morphology, 209 ; 



a basis of classification, 210; relates groups of organisms, 211 ; dis- 

 tinctions of, not absolute, 285, 290 ; generalised, 250 ; suggests blood 

 relationships, 213; schemata of, 249, 291 ; cannot be considered apart 

 from physiology, 285. 



Mosaic-theory of development, 131. 



Motion 



not an intellectual concept, 27 ; not considered in Euclidean or Cartesian 

 geometry, 26 ; bodily motion is absolute, 24 ; outside ourselves is 

 relative, 24. 



Motor-habits, 38, 155. 



Multicellular organisms, evolution of, 223. 

 2b 



