Expediency, 291 Experience, 238, 241, 253, 256; learning by, 241; sensory, 238, 253 Experimentation, 197 Eye, 60, 205, 217, 283, 298; a corporal element intrinsic to the visual sense, 217; an example of convergence, 60; constituent part of agent and subject of vision, 217; human, defective, 298; not replaced by telescope, 205; vertebrate type of, 283 Factorial, complex, 45 Factors, germinal (genetic, hereditary), 5, 6, 15, 17, 18, 19, 41, 42, 44, 45, 68, 122, 151, 152, 174, 207, 291 —diagnosis of, 122 —fractionation of, 19 —positive and inhibitive, 19; environmental, 6, 41, 42, 68, 151, 152, 174, 207, 291 —blind, 151, 152 —of disuse and selection, 207 Facts, 205; former cannot be formulated except with reference to ego, 205; in terms denoting or connoting ego, 205; intramental and extramental, 205 “Falsifications” of ancestral records, 276 Families, 37, 58; chemical, 58 Family-tree, evolutionary, 58 Fats, 145 Faulting, 107, 108; horizontal and vertical, 108; “Low angle,” 107, 108; normal, 108 Fayûm, the, 115 Feldhofer Grotte, 323, 324, 326 Felis leo fossilis, 319 Femur, 313, 316, 317, 324, 327, 330, 341; not curved as in Neanderthal type, 341; shows curvature, 327, 330 Ferns, 118 Fertilization, 42, 157, 159, 160 Filiation, 75 Finality, immanent law of, 174 First causes, 52, 71, 249 Fishes, 61, 270, 276, 279, 283, 296; adult, 279, 283; embryo of, 279 Fish-kidney, 302 Fission, binary, 156, 161; unequal, 156; multiple, 156 Fixism, 4, 32, 52, 69, 70, 72, 75, 119, 124, 268; unable to furnish “natural” explanation of homology, 52; uniformitarian, 69 Flat worms, 278 Flies, 134 Fluctuants, 87 Fluctuations, 10, 16, 29, 302, 333; cause of, 10, 16; instance of, 16; non-inheritable, 10, 16 Fœtal life, special conditions of, 299 Fœtus, 301 Fonte de Gaume, 339 Foot-and-mouth disease, germ of, 183 _note_ Foramnifera, 118 Force, 172, 176; defined, 172; no special vital, 176 Forehead, 328, 330, 341; higher, 328; low, 341; retreating, 330 Formaldehyde, 145-148; not first step in origin of life nor in photosynthesis, 145-147 Formaldehyde-hypothesis, 145-148 Formaldoxime, 148 Formations, fossiliferous, 105 Formations, geological, 75, 84, 93, 95, 99, 100, 103, 105, 108, 118, 119, 126; time-value of, 84 Formed bodies of cell, self-perpetuating, 168 Formose, 145 Forms, 246, 275, 276, 312; fossil, sequence of, 276 —intermediate, 312; grammatical, 246; intermediate, none between man and apes, 275 Fortuitous result, 249 Fossil bones, 319 Fossil facts, 311