INDEX 



Acanthias. labyrinth of. Fig. 104, 

 205 



Achondroplastic dwarf, nose of, 

 169, 171; development of 

 skull in, 230 



Acorn-worm {Balanoglossus), 

 theory of relation to ancestors 

 of vertebrates, 93; larva of 

 (Toniaria), Fig. 55, 93 



Acromegaly, causes and effects of, 

 171, 231 



Adapidae, feet compared with 

 those of lemur, 54 



Adapis, skull of. Fig. 53, 85 



African pygmy, nose of, 164, Fig. 

 89, facing 170 



Alar cartilages, of mammalian 

 nose, 167; growth power of, 

 170 



Alligator, labyrinth of. Fig. 104, 

 205; ear of the, 207 



Alligator-gar, resemblance to De- 

 vonian ganoids, 23 



Allis, Edward Phelps, Jr., head of 

 shark figured by, 13 



Amblystoma punctatum, embryo 

 of, Fig. 14, 26 



Armenian, nose of. Fig. 89, 170 



Amphibia, in coal-beds of Great 

 Britain, 27; restoration of 

 Eogyrinus, Fig. 15, 28; Wat- 

 son's studies of early, 28; 

 disappearance of bony plates 

 over gill-chamber, 29, Fig. 17, 

 30, 89, 114; middle ear of 

 earliest, 29; lower jaw of, 29; 

 teeth of, 31; teeth similar to 

 those of lobe-finned ganoids, 

 31; enlargement of para- 

 sphenoid, 31; breeding habits 

 of, 32; development of, 32; 

 period of dominance of. Fig. 

 25, 46; man's debt to, 89; 

 primary upper jaw becomes 

 attached to skull. 104, Fig. 62, 



105; covering of primary jaws 

 in early, 106; skull compared 

 with that of crossopt, 107, 

 Fig. 63, 108; close relatives of 

 osteolepid crossopts, 114; 

 elimination of internal gills 

 in adult stage, 114; feeding 

 habits of, 114; unspecialized, 

 nearest to line of ascent to 

 man, 115; respiration of, 118, 

 158; naso-buccal channel of, 

 122; tongue of, 123; first true 

 ear in, 207; section of head of. 

 Fig. 106, 208; otic notch of, 

 209; stapes of, 216; tym- 

 panum of, 216, 217; Jacob- 

 son's organ in, 158 



Amphioxus, entire animal and 

 transverse section of. Fig. 

 54, 92; as descendant of 

 ancestral stock of vertebrates, 

 93; ingestion in, 95; "ciliated 

 groove" of pharynx, 98; 

 mouth of, 129; light cells of. 

 Fig. 96, 183; spinal cord 

 (section), Fig. 96, 183 



"Ampullae" of shark. Fig. 6, 13, 

 16, 204, 206 



Anaspida, Fig. 4, 11, 96 



Andrews, Roy C, discovery of 

 Cretaceous mammals by, 51 



Angular bone, evolution of. Fig. 

 52, 82; of Trimerorhachis, Fig. 

 64, 111; of Megalichthys, Fig. 

 64, 111; of mammal-like 

 reptiles, 218 



Animalcule, slipper (Paramoe- 

 cium), Fig. 1, 5 



Anteater, Spiny (Echidna), mouth 

 of, 131 



Anthropoid, human dentition de- 

 rived from that of, 57; 

 development of the eye in, 65; 

 face influenced by erect 

 posture of, 66; date of man's 



261 



