Ceph"laspis, resem"lance to Arthropod, 29
Ceph"laspis, segmentation, 339
Ceratodus, 148
Cephalization, 51
Cephalodiscus, 438
Cephalopod, 23
Chætopoda, 395
Chamber, oral, of Ammocœtes, 243, 287, 458
Cheliceræ, 235
Chiasma, optic, 101
Chilaria, 235, 238, 291, 301, 458
Chitin, 85, 119, 139, 205, 206, 302, 329, 346, 359, 440, 443
Cilia, 206
Circulation, branchial, 174
Cirri, 357
Clarke's column, 467
Clepsine, nephridial glands, 423
Cochlea, 378
Cœlolepidæ, 344
Cœlom, 167, 251, 400, 472, 481
Cœlomata, 472
Colleneytes, 474
Commissure, anterior, 49
Comm"ssure, œsophageal, 14
Comm"ssure, posterior, 48, 280
Comparison of brains of Ammocœtes and Arthropod, 61
Comp"rison of br"ins of invertebrate from Branchipus to Ammocœtes, 54
Comp"rison of br"ins of vertebrate, 40
Comp"rison of branchial circulation in Ammocœtes and Limulus, 174
Comp"rison of bran"hial lamellæ of Scorpion and Ammocœtes, 175
Comp"rison of bran"hial segments of Ammocœtes and Petromyzon, 169
Comp"rison of Cephalaspidian and Palæostracan fish, 31
Comp"rison of Cœlom of Peripatus and Vertebrate, 400
Comp"rison of dermal covering of Pteraspis with chitin of Limulus or dentine of fish scales, 346
Comp"rison of entosternite or plastron of Limulus with trabeculæ of Ammocœtes, 145
Comp"rison of excretory organs of vertebrates and invertebrates, 389
Comp"rison of gut of Arthropod and tube of central nervous system of Vertebrate, 43, 244, 433, 440, 455, 457
Comp"rison of head-shield of Cephalaspis and Ammocœtes, 291, 329, 338
Comp"rison of hypophysial tube with olfactory tube of Arthropod ancestor, 229
Comp"rison of hypop"ysial t"be with position of palæostoma, 317
Comp"rison of mesosomatic region of Ammocœtes and Eurypterus, 192
Comp"rison of muscles, branchial, of Ammocœtes and appendage muscles of Scorpion, 171, 447
Comp"rison of mu"cles, eye, of Vertebrate with dorso-ventral muscles of Scorpion, 267, 272, 459
Comp"rison of mu"cles, of oral chamber of Ammocœtes and prosomatic musculature of Limulus, 247, 447
Comp"rison of mu"cles, longitudinal body-muscles of Vertebrate and dorsal longitudinal muscles of Arthropod, 411, 447
Comp"rison of nerves, appendage of Limulus and Branchipus to lateral root system of Vertebrate, 157
Comp"rison of ne"ves, cranial and spinal segmental, 152
Comp"rison of nervous systems of Vertebrate and Arthropod, 36
Comp"rison of pineal gland of vertebrates and median eyes of Arthropod, 63, 456
Comp"rison of pituitary body and coxal glands, 246, 319, 321
Comp"rison of prosoma and mesosoma of Limulus and Ammocœtes, 140, 141
Comp"rison of prosomatic region of Ammocœtes and Eurypterus, 244, 333
Comp"rison of retina in Ammocœtes and Musca, 97
Comp"rison of re"ina compound in Arthropod and Vertebrate, 87
Comp"rison of skeleton of Limulus and Ammocœtes, 126, 136
Comp"rison of sense-organs of Arthropod appendages with auditory organs of Vertebrate, 375
Comp"rison of thyroid with endostyle, 198
Comp"rison of thy"oid w"th uterus of Scorpion, 205
Corneagen, 69
Corpora quadrigemina, 47
Corpuscles, Pacinian, Herbst, Grandry, etc., 470
Coxal glands, 242, 246, 319, 321, 389, 398, 403, 429
Crest, neural, 281
Cromatophores of frog, 470
Crura cerebri, 14
Crustacea, first appearance, 27
Crust"cea, retina, 100
Crust"cea, segmental glands, 422
Ctenophora, 474
Cyclostomata, 165, 229, 343, 353, 424
Cysts, 50
Daphnia, 112
Degeneration, 17, 19, 59, 74, 78, 94, 107, 212, 309, 333, 336, 343
Deiters' nucleus, 489
Dendrites, 72
Development, parallel, 497
Devel"pment, of two types of eye, 73
Devel"pment, vertebrate retina, 101
Digestion, 441
Dinosaurs, 17
Diverticula, optic, 102
Drepanopterus Bembycoides, 238
Ectognath, 238, 242, 271, 304, 342, 381
Eel, 488
Elastin, 435
Embryo, head of dogfish, 121, 123
Em"ryo, skull of pig, 121
Embryology, principles of, 455
Encepalomeres, 262
Entapophysis of Limulus, 139
Enterocœla, 472
Entochondrites, 377
Entosternite, 143
Epithelium cells of Ammocœtes, 347
Epith"lium of central nervous system of vertebrates, 38, 457
Epith"lium of cœlomic spaces in annelids, 421
Epith"lium of optic diverticula, 103
Epith"lium of peritoneal, pleural, and pericardial cavities, 477
Epith"lium of velum of Ammocœtes, 301, 302
Equilibration, 358
Eukeraspis, 326
Eury"terus, appendages, 150, 236, 237
Eury"terus, classification, 249
Eury"terus, comparison with Ammocœtes, 170, 323
Eury"terus, diagram of sagittal median section, 240, 245
Eury"terus, endostoma, 241, 306
Eury"terus, eyes, 275
Eury"terus, mesosomatic segments, 192
Eury"terus, muscles of carapace, 269
Eury"terus, operculum, 150, 190, 212
Evidence of alimentary canal, innervation, 446
Evide"ce of auditory apparatus and lateral line organs, 355
Evide"ce of cœlomic cavities in Limulus, 251
Evide"ce of degeneracy in Ammocœtes, 59, 94, 343
Evide"ce of embryology, cartilage, 20, 129
Evide"ce of embry"logy, eye-muscles, 263
Evide"ce of embry"logy, excretory organs, 390
Evide"ce of embry"logy, heart, 179, 451
Evide"ce of embry"logy, nervous system, central, cerebral vesicles, 48, 458
Evide"ce of embry"logy, ner"ous sy"tem, ce"tral, epithelial tube, 37, 42, 102, 244, 433, 455
Evide"ce of embry"logy, ner"ous sy"tem, ce"tral, neurenteric canal, 37
Evide"ce of embry"logy, ner"ous sy"tem, ce"tral, neuropore, 220, 457
Evide"ce of embry"logy, ner"ous sy"tem, ce"tral, optic diverticula, 102
Evide"ce of embry"logy, ner"ous sy"tem, ce"tral, spinal cord, 46
Evide"ce of embry"logy, oral chamber, 228, 242, 243, 290
Evide"ce of embry"logy, olfactory organ, 220, 227
Evide"ce of embry"logy, palæostoma or old mouth, 317
Evide"ce of embry"logy, pineal or median eyes, 15, 63, 74, 456
Evide"ce of embry"logy, pituitary body and coxal glands, 246, 319
Evide"ce of embry"logy, thyroid, 192, 194
Evide"ce of embry"logy, segmentation, double, of head, 157, 234, 258
Evide"ce of embry"logy, skeleton, cranial, 120, 153
Evide"ce of nervous system, central, 8
Evide"ce of notochord, origin from segmented region, 443
Evide"ce of olfactory apparatus, 218
Evide"ce of organs of vision, 68
Evide"ce of palæontology, 20, 497
Evide"ce of pineal or median eyes, 74
Evide"ce of prosomatic musculature, 247
Evide"ce of respiratory apparatus, 148
Evide"ce of segmentation in head-shield, 339
Evide"ce of skeleton, 119
Evolution, 8, 15, 20, 149, 482, 497
Evol"tion, of brain in brain-case, 210
Evol"tion, of cranium of Vertebrate, 342
Evol"tion, of excretory organs, 389
Evol"tion, of eye of Vertebrate, 114
Evol"tion, of nervous system, central, 34
Evol"tion, of tissues, 19
Evol"tion, of Vertebrate from Balanoglossus and Amphioxus, 33
Eyes, 68
Ey"s, median or pineal, 74, 77, 78, 79
Fat-cells in muco-cartilage, 332
Fat-column of Ammocœtes, 181, 182
Fibres, Mauthnerian, 488
Fib"rs, Müllerian, of Ammocœtes central nervous system, 489
Fib"rs, Müll"rian, of retina, 96, 107
Fishes, classification, 218
Fis"es, ancient, classification, 326, 343
Fis"es, ani"ent, cloacal region, 450
Fis"es, ani"ent, dominance, 23
Fis"es, ani"ent, eyes, 75
Fis"es, ani"ent, head-shields. See Head-shields
Fis"es, ani"ent, pleural folds, 414
Fissure, posterior, 43
Flabellum, 359, 360, 362, 363, 366
Function of auditory organ, double, 358
Funt"ion of lateral line sense-organs, 357
Funt"ion of nerves, 448
Fusion of ganglia, 52
Galeodes, 230
Gale"des, brain, and camerostome, 222, 223
Gale"des, primordial cranium, 341
Gale"des, racquet-organs, 369, 375
Ganglia, infraœsophageal, 4, 12, 14, 51, 221
Ganl"ia, supraœsophageal, 4, 12, 14, 49, 52, 221, 225
Ganl"ia, origin of, of cranial and spinal nerves, 281
Ganglion, epibranchial, 164, 282
Ganl"ion, optic of retina, 72, 89, 97
Ganl"ion, of posterior root, 466
Ganl"ion, cells of sympathetic system, 424, 428, 448
Genital corpuscles, 470
Geological record, 20
Geol"gical strata, 22
Geotria australis, 80
Germ-band, 482
Germ-cells, 471
Giant-fibres, 489
Gills, 148, 161, 185, 214, 494
Glabellum, 339
Glands, carotid, 427
Gla"ds, coxal, 242, 246, 319, 321, 425, 429
Gla"ds, ductless, 418
Gla"ds, generative, of Limulus, 209
Gla"ds, internal secretion of, 214
Gla"ds, lymphatic, 418
Gla"ds, pineal, 15, 63, 75, 456
Gla"ds, pituitary, 244, 246, 319, 425
Gla"ds, segmental, of Crustacea, 422
Gla"ds, submaxillary, 466
Gla"ds, sweat, 448
Gla"ds, thymus, 425
Gla"ds, thyroid, of Ammocœtes, 193, 194, 196, 201, 205, 429
Gla"ds, tissue round brain of Ammocœtes, 209, 379
Gla"ds, uterine, of Scorpion, 202, 203, 204, 205
Goitre, 215
Grooves, ciliated, 188, 197, 212
Gro"ves, hyper-pharyngeal of Amphioxus, 410
Gro"ves, ventral, of apus and trilobites, 436
Gymnophiona, 393
Hæmocytes, 472
Head of embryo dogfish, 121, 123
Head-shield, dorsal, of Ammocœtes, 330, 331, 338
Head-s"ield, dor"al, of Auchenaspis, 29, 31, 338
Head-s"ield, dor"al, of Cephalaspis, 327, 328, 330, 338, 348
Head-s"ield, dor"al, of Cyathaspis, 340
Head-s"ield, dor"al, of Didymaspis, 338
Head-s"ield, dor"al, of evidence of segmentation, 339
Head-s"ield, dor"al, of Keraspis, 328