514 
Monoceros, *223. 
Monocondylea, *434. 
Monodacna, 454. 
Monodonta, *265. 
Monecious, 40. 
Monomyary, 402. 
Monopleura, *438. 
Mono-pleuro-branchiata, 
312. 
Monoptigma, *240. 
Monoptigma, 239. 
Monoptygma, 313. 
Monotis, *417. 
Monstrosities, 37. 
Montacuta,*460. 
Montagua, 335. 
Mopasha, 284. 
Morio,; 225. 
Morrisia, *367. 
Morum, 225. 
Mouretia, 281. 
Mulinia, 477. 
Mulleria, 432, *435. 
Multispiral operc., 208. 
Munsteria, 182. 
Murchisonia, *270. 
Murex, 23, 35, 36, *213. 
Muricide, *212. 
Muscular system, 18, 355, 
401. 
Musculium, 461. 
Mutela, 435. 
Mya, *489. 
Myacide, *489. 
Myacites, *497. 
Myadora, *499. 
Myalina, *421. 
Myatella, 498. 
Mycetopus, *435. 
Mycetopus, 435. 
Myochama, *499. 
Myoconcha, *471. 
Myonia, *241. 
Myoparo, 427. 
Meenas, *431, 
Myopsis, 497. 
Myrina, *423. 
Myristica, *217. 
Mysia, 475. 
Mylilita, 459. 
Mytiuicardia, 471. 
Mytilide, *420. 
Mytilimeria, *422. 
Mytilomya, 423. 
Mytilus, 30, 31, 43, *420. 
Myzxostoma, 308. 
WNacca, 235. 
Nacella, *280. 
Nacreous shells, 29, 
Nanina, 290. 
Narantio, 476. 
Narica, *237. 
Nassa, *221. 
Natica, 38, *235. 
Naticella, 236. 
Naticide, *235. 
Naticina, *236. 
Naticopsis, *235, 
INDEX. 
Natural barriers, 53. 
Natural history provinces, 
50—54. 
Nautilide, *185. 
Nautiloceras, 194. 
Nautilus, 161. 
Nautilus, 55, 185. 
Navicella, *262. 
Neera, *491. 
Neda, *323. 
Nelo, 429. 
Neithea, *412. 
Nematura, *256. 
Nerinza, *244, 314. 
Nerinella, *244., 
Nerita, 38, 55, *260. 
Neritide, 36, *260. 
Neritina, 37, *261. 
Neritoma, *261. 
Neritopsis, *261. 
Nervous system, 16. 
. Nets, 139. 
Neverita, 236. 
New Zealand shells, 104. 
Nidamental ribbon, 40. 
Niphonia, 267. 
Niso, *240, 
Noetia, 427. 
Nomenclature, 48, 
Northia 221. 
Notarchus, *321. 
Nothoceras, *195. 
Notoceeli, *174. 
Notomya, 469. 
Novaculina, *489. 
Nucinella, 427. 
Nucleobranchiata, 340. 
Nucleus, 205. 
Nucula, *426. 
Nucula, *497. 
Nuculina, *427. 
Nucunella, 427. 
Nudibranchiata, *325. 
Obeliscus, 238. 
Obolus, *392. 
Octopoda, *158. 
Octopodoteuthis, 171. 
Octopus, 56, *163. 
Ocythoe, 161, 
Odoncinetus, 495. 
Odontidium, 249. 
Odontostomus, *291. 
Odostomia, *239. 
Oleacina, 292. 
Oligyra, 310. 
Oliva, 32, 55, *227. 
Olivancillaria, 227. 
Olivella, *227. 
Olivia, 265. 
Omala, 480. 
Omalazis, 253. 
Omalia, 475. 
Omalonyx, *291. 
Ommastrephes, *172. 
Omphalotropis, 307. 
Oncidiade, *299. 
Oncidium, *299., 
Oncidoris, *329. 
- Oncoceras, *193, 
Oniscia, #225. 
Onustus, 254. 
Onychia, 171. 
Onychochi‘on, 284. 
Ouychoteu ‘his, *171. 
Operculata, *305 
Operculum, 38, 182, 237. 
Ophileta, 267. 
Opis, *470. 
Opistho-branchia, *311. 
Opisthophorus, *309. 
Orbicelia, 389. 
Orbicula, 358, 386, 388. 
Orbiculoidea, 388. 
Orbis, *253. 
Orbulites, 187. 
Oregon, shells of, 109, 
Ormoceras, *191. 
Ornati, *198. 
Orthambonites, 380. 
Orthide, *379. 
Orthis, *380. 
Orthisina, *380. 
Orthoceras, 38, *190. 
Orthoceratide, *190. 
Orthona, 336. 
Orthonotus, *423, 
Orthothriz, 385. 
Oscanius, 322. 
Osteodesma, 495, 
Ostrea, 31, *407. 
Ostreide, *407. 
Otina, *238. 
Otolithes, 17. 
Otopoma, *307. 
Oviducts, 359. 
Oviparous repr., 40, 
Ovulum, 27, *234. 
Ovum, 41. 
Owenta, 169. 
Oxygyrus, *344, 
Oyster shell, 31. 
Pachydomus, *469. 
Pachylabra, 258. 
Pachymya, 492. 
Pachyodon, 434, 470. 
Pachyotis, 291. 
Pachyrisma, *470, 
Pachytes, 414. 
Pachytoma, 310. 
Pacyodon, 490. 
Padollus, 268. 
Pagodella, 252. 
Paleoteuthis, 177, 182. 
Pallia: impression, 20. 
Pallial line, 404. 
Pallial sinus, 404. 
Pallio-branchiata, 354. 
Pallium, *412. 
Paludestrina, 254, 
Paiudina, 27,37, *257, 286 
Paludinella, 256. 
Paludinide, *257. 
Paludomus, *247. 
Panama shells, 81. 
Panamic province, 79. 
Pancreas, 23. 
