INDEX 



Shark, Devonian — (Continued) 

 facing 12; instruments of pre- 

 cision in head of. Fig. 6, 13, 

 14; olfactory capsules of. Fig. 

 6, 13, 14; Fig. 7, 17, Fig. 81, 

 155; eye muscles of. Fig. 6, 

 13, 15; shark nearer to man 

 than to invertebrates, 14, 

 102; and his prey, 15; taste 

 organs of, 16; "ampullse" in 

 head of, 16, 204; "internal 

 ears" of, 16; cartilaginous 

 skeleton of head of. Fig. 7, 

 17; primary jaws of. Figs. 7, 

 8, 17, 18, Fig. 62, 105; 

 palatoquadrate of. Figs. 7, 

 8, 17, 18; labial cartilages of, 

 Figs. 7, 8, 17, 18; hyoid of. 

 Fig. 7, 17; hyomandibula of. 

 Figs. 7, 8, 17, 18; jaw 

 muscles of. Fig. 8, 18, Fig. 

 61, 103; derivation of jaw 

 muscles of, 104; otic capsule 

 of. Fig. 7, 17, Fig. 81, 155; 

 optic capsule of. Fig. 7, 17; 

 skin of the, 19; chemical 

 composition of skeleton of, 

 23; facial expression of, 19; 

 mouth pouches of embryonic, 

 94; three stages in develop- 

 ment of teeth of. Fig. 60, 99; 

 visceral arches in predecessors 

 of, 104; mouth pouches sup- 

 ported by cartilaginous bars, 

 104; secondary jaws repre- 

 sented only by skin, 106; 

 development of teeth in typ- 

 ical, 109; less advanced than 

 crossopt, 113; tongue of, 123; 

 dissection of head of. Fig. 

 81, 155; oronasal groove of. 

 Fig. 66, 121, 154, 157; method 

 of respiration of, 122; mouth 

 of, 130; spiracle of. Fig. 81, 

 155; eye of, nearer to that of 

 man than to any invertebrate 

 eye, 191; horizontal section of 

 eye of. Fig. 99, 192; laby- 

 rinth of. Fig. 104, 205 



Shark-like stage, of human eye, 

 191 



Shoulder-girdle, Watson cited on, 

 of fossil amphibians, 28, Fig. 

 15, 28 



Shrew, see Tree-shrew 



Shylock, and the shark, 12 



Silurian and Devonian ostraco- 

 derms, 10, Fig. 4, 11; Kiser 

 and Stensio cited on, 10, 11, 

 12, 94, 97, 98; Lanarkia, 100 



"Simian shelf" of Piltdown man. 

 Fig. 45, 71, 143 



Sinus, nasal, of man and anthro- 

 poids, 161, 162; frontal, con- 

 nection with nasal meati. 

 Fig. 85, 163; ethmoid, con- 

 nection with nasal meati. 

 Fig. 85, 163; sphenoid, con- 

 nection with nasal meati. 

 Fig. 85, 163 



Sivapitkecus, traces of derivation 

 of human dentition from, 

 58; lower jaw of. Fig. 37, 61; 

 dental formula of, Fig. 37, 

 61; front lower premolars of, 

 144, Fig. 75, 144; upper 

 molars of, 140 



Skeleton, of shark, its chemical 

 composition, 23; of Noth- 

 arctus. Fig. 32, facing 54 



Skin, of shark, 19; potentialities 

 of, 100; structures derivative 

 from, 101; origin of some 

 sense organs in, 101; origin 

 of teeth in, 101, 109; dentary, 

 maxillae and premaxillse of 

 advanced crossopts covered 

 by, 130; on bill of Platypus, 

 131 



Skull, heritage of the, 20, 28, 89; 

 structure of the, 21, 83; 

 comparison of lobe-finned 

 ganoid, with early amphibian, 

 29, 107; simplification of the, 

 31; formation of mammalian 

 joint of, 39, 90; of some 

 placental mammals ap- 

 proaches that of lowest Pri- 

 mates, 53; dominant elements 

 of human, 87; evolution of 

 human, from fish to man. 

 Figs. 48-53, 78-85; changes 

 in lateral view of, from fish 

 to man, 86-91; factors deter- 

 mining changes in structure 

 of, 88-89; genesis of temporal 

 bone of, 88; loss of bones cov- 

 ering branchial chamber of, 

 89; changes of, in arboreal 

 pro-anthropoids, 91; attach- 



289 



