476 



INDEX 



otolith of, 353 

 Morays, Fig. 82 



dentition of, 423 



morphological features of, 202 



neurocranium of, 438 



number of gills in, 424 



opercular elements in, 426 

 Mormyroidea 



eyes' in, 170,439 



mouth in, 417 



origin of, 174 



otoliths of, 174 



relations of, 173 



specializations of, 167 



swim-bladder in, 169, 174, 439 

 Mormyrops, Fig. 62 

 Mouth, see also Protrusility 



adaptive radiation of, 415 



of Allotriognathi, 296 



of Ammodytoidei, 354 



of carps and suckers, 189 



of Chcttodon, 279 



embryonic and larval stages of, 422, 439 



evolution of different types of, 85, 416, 

 444 



of Mola, 295 



position and direction of, 416 



relation of, to jaws and suspensorium, 

 418 



size of, 416 



of Symbranchii, 352 



of Xesurus, 283 

 Mouth region 



dimensional factors in, 419-423, Figs. 

 286-289 

 Muciferous channels, 252 

 Mugil, Figs. 138, 143 



premaxilla of, 242 



skull of, 263 

 Mullets, see Percesoces 

 Mullidje, 251 

 MuUus 



otoliths of, 251, 277 

 Myctophidae 



otoliths of, 212 

 Myctophum, Fig. 93 



Myoxocephalus, Figs. 213, 215, 293, 299 

 Myripristis, 235, Fig. Ill 



N 



Naef, Adolf 



on origin of amphibians, 105 

 Natural Selection, 320, 449 

 Needle-fish, see Synentognathi 

 Nematognathi 



air-bladder of, 196 



cranial buckler of, 441 



mouth of, 416 



skin of, 441 



specializations of, 195 

 Neohythites 



otoliths of, 353 

 Neopterygians 



otoliths of, 321 

 Nfotkunnus, 319 



Nerophis, 226 



Neurocranium, see also Skull, Syncranium 



adaptation to food types, 431 



adjustment to body, 431 



adjustment to jaw and mouth, 438 



adjustment to skin, 441 



bones of, 88, 89 



cranial vault of, 435^38 



definition of, 431 



description of, 434, 435 



differential growth rates of, 432, 434, 

 Figs. 294, 297 



differentiation of, from branchiocran- 

 ium, 77, Fig. 1 



ectosteal bones of, 442 



endosteal bones of, 442 



functions of, 435, 443 



of Hemitripterus, Fig. 215 



of Lophius, 396 



mechanism of, in acanthopterids, 242 



moulded bv diverticula of swim- 

 bladder, 439 



moulded by eyes, 439 



of onchocephalids, 397 



of percoids. Fig. 298 



of scorpaenoids. Fig. 299 

 Nfxilosus, Fig. 127 

 Noble, G. K., 454 

 Nomenclature 



Gregory on, 91, 92 



Kesteven's variations in, 95, 96 

 Norman, J. R., 260 

 Notacanthidse 

 Notacanthus 



otolith of, 201 

 Nolelops, 166 

 Notidanoids, 424 

 Notogoneus 



characters of, 179 



Woodward on, 175 

 Notopterida;, 170, 173 

 Notopterus, Fig. 168 



adjustment of skull of, with body form, 

 168 



chondrocranium of, 173 



otolith of, 170 



primitive character of, 174 

 Nololhenia, Figs. 237, 239, 240, 241 



pectoral girdle of, 362 



skull measurements of, 360 



Trachinus not close to, 363 

 Nototheniiformes 



Regan's classification of, 358 



otoliths of, 360 

 Notothenioids 



Regan's classification of, 358 



origins of, 360 

 Nuchal shield, 195 



O 



Oar-fish, see Allotriognathi 

 Occipital condyle 



in Gonorhynchus and Fistularia, 178 

 Odonteithes, 264 



Odontostomus, Fig. 91 

 Ogcocephalidas, 387 

 Ogcocfphalus, Figs. 269, 270 



opercular of, 401 



skull of, 397 

 Olfactory sacs 



of Haplophryne, 407 

 Oligoplites 



characters of, 301 



comparison with Coryphsena, 305 



fins of, 301 

 Omosudidae, 207 

 Omoiudis, Fig. 89 



dentition of, 423 



mouth of, 416 



re.'iemblances of, 204 

 Onchocephalids 



characters of, 397 



derivation of, 398 

 Oneirodes, Fig. 279 



description of, 407 



illicium of, 409 

 Opah, see Allotriognathi 

 Opercular elements 



in Acanthopterygii, 426 



of Bovichthys, Fig. 240 



"circumorbital" arrangement of, 428 



of Cottoperca, Fig. 240 



embryology of, 427 



origin of series of, 84 



in primitive teleosts, 135 



variability in, 427 

 Opercular spines 



in acanthopts, 234 

 Ophichthys, V>1 

 Ophidiids, 349 

 Ophiocephaloidea, 269 

 Ophiocfphalus, Figs. 145, 146 



comparison with Uranoscopus, 367 



opercular elements in, 426, Fig. 145 



otolith of, 269, 271 



resemblance of, to typical anacanth 

 skull, 381 



skull of, 269 

 Ophidiids, 379 

 Ophiodon, Fig. 210 

 Opisthomi, 353 

 Opisthoproctus, Fig. 43 



auditory capsules of, 440 



comparison with Clenothrissa, 151 



eyes in, 439 

 Opsanus, Fig. 263 



skull of, 382 

 Oreslias, Fig. 97 

 "Organizers," 447 

 Orobranchial apparatus 



in gnathostomes, 82, 83 



Goodrich on, 83 



in ostracoderms and cyclostomes, 77, 79 

 Osbom, Henry Fairfield 



on "rectigradations," 446 

 Osmeroides, 138 

 Osmerus, 157 



otolith of, 212 

 Osplironemus, Fig. 147 



