INDEX 



(References to figures in Clarendon type) 



Abapical, 4 

 Abdominal pores, 251 

 Acanthias — ■ 



brain, 92, 93 



chondrocranium, 313 



egg-shell, 478 



heart, 374 



liver, 187 

 , muscle-buds, 208 



spinal ganglia, 12? 



spines, 322 

 .4 cipenser — 



arcualia, 295 



cement-organs, 180 



egg, 23 



gill-lamellae, origin, 160 



segmentation, 23, 24 

 Acrochordal cartilage, 315 

 Actinopterygii — 



gastrulation, 46 



nares, 125 



pyloric caeca, 191 



segmentation, 19 

 Adrenal, 282 

 Air-bladder — 



evolution of, 173 



of Teleosts, 166, 167 

 Air-sacs, 164, 165 

 Allantoic vein, 423 

 Allantois, 242, 471, 476, 549 

 Alytes — 



oviposition, 461 

 A mbly stoma ( = Siredon = Axolotl )- 



arcualia, 296 

 % eye, 141 



gonad, 269, 272 



vertebral centra, 300 



vomer with teeth, 332 

 Amia — 



air-bladder, 168 



cement-organs, 178, 181 



segmentation, 24 



vertebrae, 297, 339 

 Amnion, 465 



evolutionary origin, 475, 476 



Amniota — 



buccal cavity, 148 



Amniota (continued) — 



external gills, physiological replacement 

 of, 157 



gastrulation, 47 



haemal arches, 297 



nares, 126, 151 



sclerotome, 205 

 Amniotic isthmus, 469 

 Amphibia — 



adaptations in early development, 458 



egg, 2, 27 



endolymphatic duct, 132 



gastrulation, 38 



gonad, 268 



heart, 389 



mesoderm, origin, 60 



opisthonephros, 251 



pharyngeal clefts, 159 



practical hints, 566 



pronephros, 235 



segmentation, 27 



testicular network, 279 



vertebral centra, 299 

 Amphioxus — 



brain, 96 



egg, 2, 3 



gastrulation, 30, 31 



gonad, 267 



liver, 186 



mesoderm, origin, 57 



practical hints, 558 



sclerotome, 285, 286 



segmentation, 7, 8, 9 

 Ampulla, 130 



Ancestry of Vertebrata, 503 

 Anura — 



cement-organs, 80 



horny jaws, 75, 76 



oral combs, 75, 76 

 Anus, 51, 144, 192, 194, 497 

 Aortic arches, 394, 395, 396, 397, 398, 401 

 Apical, 4 



Archencephalon, 85, 92 

 Archenteron, 30 

 Archinephric duct, 221, 225, 238, 239, 240, 



241 

 Archinephros, 221 



583 



