55o 



INDEX 



Myxicola, 338 ; tori uncinigeri, 268 ; eyes, 

 272 ; otocyst, 273 ; tube, 285 ; sup- 

 posed mimicry, 294 



Myzostoma, anatomy, 342 f. ; M. cirriferum, 

 343 ; M. glabrum, 342 



Myzostomaria, 241 ', structure and affini- 

 ties, 342 f. 



Myzostomatidae, 342 



Naidomorpha ( = Naididae and Naids), 

 348, 352, 375 f., 377, 378, 400 ; chaetae, 

 350, 367 ; reproductive organs, 361 ; 

 asexual reproduction, 281, 377 



Nais, 348, 377 ; chaetae, 350 



Nannodrilus, 382 f. 



Natatory chaetae, of Nereidae, 277 ; of 

 Syllidae, 278, 307 



Nathusius, on parasites, 63, 163 



Nauphanta, 314, 315 



Nebalia, Eotifers parasitic on, 225 



Nectochaeta, 291 



Nectoriema agile, 164, 168, 169, 173 



Nemathelminthes, 123 f, ; 168 



Nematobothrium, 4, 55, 71, 73 



Nematoda, 123 ; anatomy, 124 f. ; embry- 

 ology, 135 ; classification, 136 ; life- 

 history of, 159 f. 



Nematogen, 94 ; Secondary Nematogen, 94 



Nematomorpha, 123, 164 f. 



Nematoxys, 139, 142, 161, 163 



Nematozoa, 137 



Nemertes, British species, 110 ; deposition 

 of ova and spermatozoa in, 116 



Nemertinea, affinities, 119 ; anatomy, 102 ; 

 body- wall, 102 ; breeding, 116 ; cephalic 

 slits and cerebral organs, 107, 273 ; circu- 

 latory system, 106, 107 ; classification, 

 109 f. ; colour, 102 ; contractility, 102 ; 

 development, 113 ; diagram, 104 ; 

 digestive system, 103 ; excretory system, 

 108, 108 ; external characters, 101 ; 

 food, 115 ; fresh-water forms, 101, 118 ; 

 generative organs, 109 ; geographical 

 distribution, 117 ; habitat, 100 ; habits, 

 114 ; land forms, 101, 117 ; locomotion, 

 114, 115 ; nervous system, 105, 106 ; 

 parasitic forms, 101, 119 ; pelagic forms, 

 101, 114 ; proboscis, 100, 101 f., 103, 

 104, 110, 115 ; regeneration, 115 ; sense 

 organs, 101, 106, 107 ; size, 100 



Nemertodrilus, 360 



Nemertoscolex, 444 



Neodrilus, 384 



Neorhynchidae, 184 



Neorhynchus clavaeceps, 178, 181, 184', 

 N. agilis, 184 



NepMis, 392 f., 397, 399, 401, 403, 405 



Nephridium, of Archiannelida, 243, 244 ; 

 of Nereis, 253 ; of Arenicola, 253, 254 ; 

 of Polychaeta, 253 ; dimorphism of, in 

 Polychaeta, 269 ; thoracic, of Sabelli- 

 formia, 306 ; of Terebellidae, 327 ; of 



Chlorhaemidae, 334 ; of Myzostom^ 

 344 ; of Oligochaeta, 356 f., 381 f., 

 400 ; of Leeches, 399 ; of Gephyrea 

 see Brown tubes ; of Phoronis, 456 



Nephthydidae, 258, 317 



Nephthys, 317 ; nephridium, 254 ; pro- 

 stomium, 259, 260 ; head, 262 ; tentacles, 

 262; peristomium,263; parapodium, 264, 

 265 ; cirrus, 265 ; gill, 268 ; jaws, 270 ; 

 habitat, 286 ; as bait, 297 



Nereidae, 258, 315 ; palps. 260 ; colour, 

 292 



Nereidiformia, 258, 303 ; vascular system, 

 252 ; anal cirri, 259 ; prostomium, 259, 

 260 ; tentacles, 262 ; peristomial cirri, 

 263; parapodium, 264 f. ; cirri, 265; 

 chaetae, 266 ; jaws, 269 ; eyes, 272 ; 

 ciliated organ, 273 ; regeneration in, 

 283 ; food, 296 ; fossil, 301 f. 



Nereilepas, 317 



Nereis, 246, 299, 301, 316 f . ; anatomy, 



245 f., 247 f. ; transverse section, 247 ; 

 parapodium, 246, 247, 265, 317; chaetae, 



246 ; head, 246, 248, 316 ; alimentary 

 canal, 249 f., 251 ; jaws, 248, 250, 270, 

 316 ; nervous system, 254, 255 ; eye, 

 255 ; vascular system, 247, 251 ; dorsal 

 ciliated organ, 247, 254, 256 ; nephri- 

 dium, 253 ; reproduction, 256 ; sexually 

 mature, 276, 276 f. ; sexual dimorphism 

 and Heteroneid phase, 276 f. ; epitokous 

 ( = epigamous) and atokous phase, 277 

 n. ; from fresh water, 284 ; burrow, 286 ; 

 pigment, 292 ; as bait, 297 : commen- 

 salism, 298 ; as host, 299 ; British 

 species, 316 f. 



Nereites, 302 



Nerine, 299, 322 ; habitat, 286 ; N. 

 vulgaris, head, 322 



Nerve plexus of Nemertinea, 103, 105 



Nervous system, of Leptoplana, 13, 14 ; of 

 Polyclads, 26, 30 ; of Planaria lactea, 

 39 ; reduced in parasitic Bhabdocoels, 

 45 ; of Temnocephala, 54 ; of Po.ly- 

 stomatidae, 56 ; of Cestodes, 75, 86 ; of 

 Nemertinea, 105, 106 ; of Nematoda, 

 127 ; of Gordiidae, 166 ; of Acantho- 

 cephala, 177 ; of Chaetognatha, 187 ; of 

 Botifera, etc., 215, 234, 237 ; of Archi- 

 annelida, 243, 244 ; of Polychaeta, 254 ; 

 visceral, of Polychaeta, 255 ; of Oligo- 

 chaeta, 353, 374 ; of Gephyrea, 416, 

 431, 437, 440, 445 ; of Phoronis, 456 ; 

 of Polyzoa, 471 



Neumann, on parasites, 164 



Neuropodium, 246, 247, 264, 265, 268 



Newton, on zoo-geographical regions, 372 



Nicolea, 328 ; gill, 329 



Nicomache, 332 ; tail, 332 ; tube, 287 ; 

 N. lumbricalis, colour, 292 ; distribu- 

 tion, 299 



Nitsche, on Polyzca, 475 n., 478, 500 



