588 EMBRYOLOGY OF THE LOWER VERTEBRATES 



:teric canal, 41. f>l. 52, 53 

 Ntnirite, 84 

 Neurobiotaxis, 121 

 Neuroblasts, 84 

 Ncuroiibrils, 85, 112, 11!' 



>glia, 84 



Neuromasts, 132 

 Neuromery, 101 

 Nt-urone, 84 



theory, 104 

 " Normal plates," 575 

 Notochord, 147, 289 

 Sototremn, 463 

 Nuclear division, synchronism of, 16, 17, 22 



Odontoblasts, 322 

 Olfactory bulb, 91 



organ, 125 



tract or peduncle, 94 



tubercle, 91 



Ontogeny, general principles, 484 

 Opaque area, 518 

 Operculum, 158 

 Opisthonephros, 221, 246 

 Optic cup, 134 



nerve, 140 

 38, 90 



thalamus, 89 

 Otocyst, 129 

 Ovary, 274 

 Overgrowth, 32 

 Oviduct (Mullerian duct), 242 



Palaeontology and Evolution, 502 

 Paludicola, larval jaws, 76 

 Pancreas, 189 



evolutionary origin, 191 

 Pander, nucleus of, 514 

 Pauizza, foramen of, 391 

 Parachordal cartilages, 307 

 Paraphysis, 87 

 Parapineal body, 97 

 Pecten, 552 



Pectoral girdle, 354, 357 

 Pellucid area, 518 

 Pelvic girdle, 355, 358 

 Periblast, 23 

 Pericardiac cavity, 200, 210 



nlio- peritoneal canal, 200 

 Periderm, 70 



>'lerm, 63 

 -.rial, 226 



fiiuin-1, 22i, 227, '251 



fun; -i-nl, 2f.l, : 



Peritoneum. 217 

 Petromyzrm (Lamprey) 



i. ilia, 294, 296, 299 

 .Isilioii, 37, 38 * 



homy tcrtli, 77 



Itor, 187 



mesodt-nn lii-Mil. -Jl I 



|M-iirar<li:ir cavity, 200 

 j.iueal eye, 99 

 practical hint,, 559 



PetrOi/i !/."/< 



thyroid, 176 

 tongue, lfl 

 \fins, 416 



1'hannx. 153 



Phyllobate, 462 



early stages, 567, 568 



egg-laying, 459, 460 



lens, 139 

 Pigment, egg, 4 



skin, 80 



Pigments, melanin, 81 

 Pineal body, 87, 96 



eye, 96, 97, 98, 99 

 Pinkus's organ, 133 

 Pipa, 461 



Pituitary body, 90, 142 

 Placenta, 465, 480 

 Placodes, nerve, 123 

 Planula, 506 

 Plasmodesms, 111 

 Platybasic, 307 

 Platy dactyl us 



gastrular lip, 49 



gastrulation, 48, 50 

 Pleural cavity, 202 

 Plexus, choroid, 91 

 Pneumatic duct, 161 

 Poison-fangs, 326, 329 

 Polar cartilage, 313, 315 

 Polypterus 



archinephric duct, 241 



blood-corpuscles, 365 



brain, 85, 95, 146 



cement-organs, 178, 179 



dorsal aorta, 363, 364, 365 



e gg 3 



external form, 430 



-trulation, 19, 32, 33 

 heart, 388 

 limb-skeleton, 353 

 lung, 169, 172, 173 

 mult- genital duct, 281 

 olfactory organ, 127, 128 

 opistlioiit-pliros, 258 

 oviduct, 278 

 pancreas, 147, 189 

 practical hints, ;'r,-j 

 pronephros, 228, 229 

 sagittal sections, 146. 147 



scales, 336 



'tome, 285 

 ntatiou, 19 



-C, 2 

 \cimiis lystem, i !;, 418 



I'i-nny, 17 



Pottanal rot, 1 i:., 147. uo 

 uciiial bod] 



I'oiidi, ciiti-ro'-.ii 1 

 I'l-imary n-11- la\ ! 

 I'l imilivt- ^'ro.ivc, 53 



plate, 



7, 519, 520 



