INDEX. 



399 



Nerves, olfactory, 76, 327 



optic, 77, 295 



origin, 72 



spinal, 280 



spinal accessory, 268, 277, 296 



superior maxillary, 326 



third, pig, 12.0 mm., 264, 268 



trigeminal, 295, 297 



vagus, 285, 29^6, 317 

 Nervous system, origin, 67 



vertebrates, 4 

 Neuraxons, 270 

 Neuroblasts, 72, 73, 270 

 Neuroglia layer, outer, 263 

 Neuromeres, pig, 6.0 mm., 246 



12 .o mm., 264 

 Neuropore, anterior, 69, 178 

 Nodulus thymicus, 27<57~295 



origin, 63 

 Notochord, anlage 'of, 55 



growth, 55 



pig, 12 .o mm., 273 . 

 17.0 mm., 305 

 20 .o mm., 315 

 24 .o mm., 336 



relation to axial mesoderm, 56 



ultimate fate, 55 



vertebrates, 4 

 Notochordal canal, 53 

 Nuclei pulpqsi, 56, 337 



(Esophagus, origin, 57 



pig, 12. o mm., 280, 285 



17.0 mm., 305, 306 



20.0 mm., 314, 317 



Olfactory nerves, origin, 76 



plate, pig, 6.0 mm., 24-9 



12 . o mm., 277 



Omentum, pig, 12.0 mm., 288, 290 

 Operculum, pig, 259 

 Optic chiasma, 292, 335 



vesicles, chick, 133, 180, 183, 202 



differentiation, 77 

 Oral plate, 58 



chick, 184 

 human, 142 

 Orange G, 383 

 Organsf*constitution of, 20 

 Otocyst, chick, 199, 200 

 general account, 78 



pig, 12.0 mm., 261, 263, 267, 293, 299 

 Ova, primitive, 26 

 Ovulation, 35 

 mouse, 161 



J 



Ovum, before maturation, 34 

 constitution, 12 

 fertilization, mouse, 163 

 gibbon, third stage, 131 

 holoblastic, 10 

 human, 34 



second stage, 128 



Peters' s, 128 

 impregnation, 38 

 isotropism of, 1 2 

 maturation, 36 

 meroblastic, 10 

 monkey, second stage, 127 

 mosaic theory of, 12 

 segmentation, 42 



mammals, 160 



mouse, 160, 185 



Palate, 311 



cleft, 91, 312 

 Panchoroid, 266, 321 

 Pancreas, general account, 107 

 pig, 12.0 mm., 290 

 24.0 mm., 337 

 Pangenesis, 29 

 Parablast, 64 



Parathyroid glands, 63, 315 

 Penis, pig, 20.0 mm., 320 

 Pericardial cavity, chick, 181, 209 



origin, 87 



Pericardial epithelium, pig, 12.0 mm., 282 

 Perichondrium, origin of, 304 

 Peritoneal membrane, pig, 12.0 mm., 286 



20. o mm., 322 



Peritoneum, pig, 20.0 mm., 322 

 Pharynx, chick, 184, 205 

 general account, 61 

 origin, 57 



pig, 12.0 mm., 237, 238, 269, 274 

 vertebrates, 3 



Pia mater, pig, 9.0 mm., 2^4 

 12.0 mm., 266 

 17.0 mm., 305 

 20. o mm., 325 



Pig embryo, anatomy, general, 228 

 7.8 mm. stage, 228 

 12.0 mm. stage, 231 

 form, external, 22 1 

 7 . 5 mm., 221 

 10 . o mm., 223 

 15.0 mm., 225 

 20. o mm., 226 

 methods of obtaining, 219 



