INDEX 



Parasphenoid, of fish, 22; enlarge- 

 ment in amphibians of, 31 



Parietal bones, evolution of. Fig. 

 49, 79; of opossum, 49; as 

 components of dermocranium, 

 83; among dominant elements 

 of human skull, 87 



Parker, G. IL, cited on hearing of 

 fishes, 206 



Parker, W. K., cited on embry- 

 ology of sturgeon, 209 



Patten, William, theory of deriva- 

 tion of vertebrates, 7, 8, 92, 

 182; cited on derivation of 

 vertebrate eye, 182 



Pecten, eyes of, 178 



Pelvic floor. Sir Arthur Keith on 

 the primate, 63 



Pelvis, evolution of primate, 63 



Pelycodus, lower jaw of. Fig. 37, 

 61; left lower and upper 

 molars of. Fig. 38, 62 



Pen-tailed tree-shrew. Fig. 30, 

 facing 52 



Perameles, formation of meniscus 

 in embryo of. Fig. 22, 38, 39 



Periotic mass, fusion of squamosal 

 bone with, in mammals, 88 



Permian period, labyrinthodonts 

 and stegocephalians of the, 

 115; Mycterosaurus, of the, 

 34; Seymouria, of the, 32 



Permocynodon, middle ear of. Fig. 

 112, 217 



Pharynx, function in respiration 

 of, 162 

 of Amphioxus, 98 

 of larval lamprey, 98 



Philtrum, of the lip, in man, 133; 

 embryonic development of 

 the, 166 



Phototropism, 174 



Physiognomy, anthropological 

 method of study of, 224; 

 Aristotle on, 220; the author 

 analyzes his own face, 225- 

 229; clinical method of study 

 of, 224; Darwin's study of, 

 223; Duchenne's study of 

 (experimental method), 223; 

 embryological study of, 224; 

 evolutionary method of study 

 of, 223; experimental method 

 of study of (Duchenne's), 

 223; genetic method of study 



of, 224; origins of modern 



science of, 222; physiological 

 method of study of, 224; 

 psychiatrist's method of study 

 of, 225; psychoanalyst's 



method of study of, 225; 

 psychologic method of study 

 of, 224; Sir Charles Bell's 

 study of, 222; study of cor- 

 relation between crime and 

 types of, 225 



Piltdown man (Eoanthropus), 

 canine tooth of, 141; char- 

 acters of, 72, 73; lower jaw of. 

 Fig. 37, 61; Fig. 45, 71, 143; 

 lower molar of. Fig. 38, 62; 

 Fig. 41, facing 66 



Pineal eye. Fig. 97, 185, 200 



Pineal organ, origin of, 187; in 

 pre-chordates, 186 



Pithecanthropus (Trinil man), 

 characters of, 72, 73; skull 

 of (side view). Fig. 42, 68; 

 skull of (top view). Fig. 43, 69 



Pituitary glands, effects of 

 diseased, 171 



Placental mammals, their fore- 

 runners from Mongolia, 51; 

 in Basal Eocene and Pale- 

 ocene of New Mexico, 52 



Planaria, eyes of, as directional 

 organs, Fig. 93, 178; head and 

 tail differentiation of. Fig. 2, 

 facing 6; location of eyes of. 

 Fig. 92, 177 



Plant life, origin in Archeozoic 

 era, 27 



Plate, L., cited on origin and 

 development of the eye, 174- 

 188; summary of literature 

 on eyes of invertebrates and 

 vertebrates, 174; on eyes of 

 Amphioxus, 183, 184; on eye 

 capsules of flatworm. Fig. 93, 

 178; on human vision, foot- 

 note, 174; on paired eyes of 

 vertebrates, 178 



Platypus, believed related to 

 some mammals of Age of 

 Reptiles, 47; mouth of, 131 



Platyrrhine monkeys, see Monkeys, 

 platyrrhine 



Platysma muscle, origin of, 43 



Pleistocene, lower, already several 

 types of man in, 73 



285 



