INDEX 



743 



Nests, 627 



Neural-arches, 414, 458; -canal, 385; 



-tube, 388 



Neurenteric canal, 399 

 Neuroglia, 417 

 Neuron, 150, 417, 418 

 Neuropodium, 158 

 Neuropore, 406 

 Neuroptera, 245, 253, 281 

 Newt, 519, 525, 543 

 Nidamental glands, 321 

 Nidicolous, 630 

 Nidifugous, 630 

 Nightjar, 635 

 Nipple, 638 

 Nitrogenous, 147 

 Noctiluca, 34 

 Nordic race, 715 

 Nose, 418, 443 

 Notidanidae, 456, 467 

 Notochord, 136, 385, 388, 392 

 Notommata, 123, 126 

 Notommatidae, 122 

 Notonecta, 257 

 Notopodium, 158 

 Notoryctes, 663, 718 

 Notoryctidae, 662, 663, 718 

 Notostrace, 208, 277 

 Nuchal plate, 591 

 Nuclear sap, 18 

 Nuclear wall, 18 

 Nucleic acid, 4 

 Nucleus, 4, 18 

 Nucula, 296, 307, 324 

 Ri/ciiphanes, 216 



Nymphon, 283 



Obelia, 58, 69, 60, 66 



Oblique muscles, 437 



Obturator foramen, 576 



Occipital bones, 483 



Occipital region, 475 



Octopoda, 325 



Octopus, 312, 325 



Odontaspis, 456 



Odontoceti, 681, 722 



Odontoid process, 570 



Odontolcae, 633 



Oesophagus, 70, 137, 141, 428, 447, 448 



Oestrus, 258 



Okapi, 696 



Okapia, 696 



Olfactory lobes, 619 



Olfactory nerves, 425 



Oligochaeta, 157, 165 



Oligolophus, 267, 282 



Ommatostrephes, 312, 322, 325 



Omosternum, 550 



Onchosphere, 109 



Oniscus, 223, 279 



Ontogeny, 14 



Onychophora, 225, 279 



Ooecium, 378 



Oostegites, 216 



Opalina, 42, 52 



Opercular bone, 480 



Opercular flap, 480 



Opercular membrane, 481 



Operculum, 376, 377, 470 ; of Limulus, 



275 



Ophidia, 568, 587, 605 

 Ophioglypha, 339, 342, 367 

 Ophisaurus, 586 

 Ophiuroid, 340, 341 

 Ophiuroidea, 339, 367 

 Ophthalmic nerves, 426 

 Opisthobranchiata, 295, 297, 324 

 Opisthocoelous, 498, 523, 526 

 Opisthogoneata, 228, 280 

 Opisthotic, 476, 571 

 Opossums, 661, 663 

 Optic-chiasma, 425, 496, 516, 517, 518; 



-ganglia, 319; -lobes, 416, 619; 



-nerve, 425; -thalami, 538; -vesicle, 



422 

 Oral-cartilages, 391 ; -cirri, 396 ; -cone, 



49; -hood, 397; -plate, 365; -pole, 



80; -tube-feet, 343 

 Orang-utan, 711, 713 

 Orbit, 437 



Orbitosphenoid bone, 476, 530 

 Orca, 681 

 Orders, 11 

 Organ of Corti, 421 

 Organism, 34 

 Organ-pipe coral, 74 

 Organs, 17, 35 

 Organs of Bojanus, 305 

 Onithorhynchus, 656, 657, 658, 717 

 Oronasal grooves, 456 

 Orthoptera, 249, 250, 251, 280 

 Orycteropodidae, 666, 720 

 Orycteropus, 669, 720 

 Oscarella, 89 

 Osculum, 84 

 Osphradium, 294 

 Ossicula auditus, 645 

 Ostariophysi, 491 

 Osteichthyes, 453, 473, 513 

 Ostia, 230 

 Osteolepidoti, 504 

 Ostracoda, 208, 277 

 Ostrea, 308 



Ostrich, 614, 618, 627, 631, 633 

 Otaria, 679, 721 

 Otariidae, 678, 721 

 Otocyst, 292, 321 

 Otolith, 406 

 Otter, 677 

 Ova, 8 



Ovary, 53 ; of Lumbricus, 154 

 Ovibos, 697, 724 

 Oviducal gland, 463 

 Oviduct, 154, 465, 539 



