414 



54. General principles of inves- 

 tigating, 54. 97. Naked mollusks 



among the Helicids, 161. 

 Monilea, 220. 352. 

 Monoceros, 100. Tooth-like pro- 



cess of, 301. 

 Monodonta, 212. 217—219. 352. 



Analogies of, 226. Characters of, 

 220. 

 Monophora, 38. 

 Monothyra, of Aristotle, 13. 

 Mulleria, 257. 



Multivalve shells, 21. 28. 399. 

 Murex, the, 63. 295. Vitulinus, 64. 



68. Magellanicus, harp-like, 65. 



68. 

 Muricanthus, structure of, 296. 

 Muricidse, 64. 295. Sub-families, 



89. 99. Diagram of affinities of, 



95. Analogies of, 112. 

 Muricinse, or whelks, 63. Circle of 



the, 64. 89. Sub-families of, 67. 



Shortness of their canal, 75. Cha- 



racters of, 295. 

 Muricidea, 296. --'- 

 Muscle, the, or Mytilus, 31. 383. 

 Mva, 257. 367. M. margaritifera, 



261. 

 Myadse, family of, 257. 260. 367. 

 Mycetopus, 380. 

 BIyochama, 375. 



Myristica, 307. M. coronata, 86. 

 Mysca, sub-genus, 276. 283. 378. 



Analogies of types of, 278. M. 



nasuta, 263. M. ovata, 263. 277. 



292. Structure of, 266. M. pic- 



torum, 278. 282. Aberrant spe- 



cies of, 285. 

 Mytilus, 31.383. 



N. 



Na'ia, sub-genus, 284. 379. N. elon- 

 gata, 286. 



Naidea, 276. 



Nassa, typical distinction of, 68. 

 300. 



Nassinje, sub-family of, 63. 69. 299. 

 Circle of. 70. Analogies of, 70. 

 112. Affinities, 95, 96. 



Natica, 234. 241. 345. 



Naticaria, 346. 



Naticella, animal of, 249. 345. 



Nat'cidffi, family of, 60. 235. 344. 

 Analogies of, 111. Structure of 

 the nerits, 159. 



Naticinae, sub-family, 241. 345. 



Nature, on the works, provisions, 

 and devices of, 41. Her ascend- 

 ing scale from imperfection to 

 perfection, 42. 44. Great circle 

 of the system of, 3. 40. 49, et seq. 

 Tenacious of her laws, 115. 

 Modes of developement of animal 

 forms, 161. 293. 



Nautilus, the, 39. 

 Navicella, 347. 

 Nebularia, 319. 

 Nematura, 197.340. 

 Nerita, 346. 

 Neritinffi, 347. 

 Neritopsis, 346. 



Nervous system of shell-fish, 29. 

 Nitidella, 151. 153. 313. 

 Nomenclature, remarks on, 92. 291. 

 Notarchus,!251. 359. 

 Novaculina, 365. 

 Nucula, 257. 259. 382. 

 Nudibranchia, naked animals so 

 termed, 6. 25. 35. Description, 



36. 50. Respiratory organs of, 



37. The tribe distinct, 40. 



Oligyra, 337. 



Oliva, 97. 132. 321. 



Olivella, 32*. O. biplicata, 82. 132. 



322. n. ' 

 Olivine, 98. 132. 321. 

 Onchidffi, marine, 56. 

 Onchidium, 190. 327. 

 Oniscia, 67. 70. 299. 

 Onustus, or carriers, 212. 217. 221. 



355. O. agglutinans, 222. 

 Orbis, fossil, 196. 

 Ostrjea, affinities of the, 47. 257. 



387—389. 

 Ostridffi, the, 257. 385. 

 Ovula, 135. 325. 



OvulinjE, or egg-shells, 135. 325. 

 Oyster, the, 27. 387. The river 



oysters, 3b9. 



Pachylabra, 339. 



Pachvtoma, 337- 



Pagodella, 207. 219. 351. 



Paludina, genus, 197. 339. P. vivi- 

 para, 197. P. impura, 198. P. 

 parvula, 198. 



Paludomus, 198. Proper, 199. 340. 



Pandora, 3r)8. 



Par,opia, 367. 



Papyridea, 374. 



Parenchymata, affinities of the, 

 4. n. Intestinal Testacea, 35.; 

 and worms, 38. Parasitic Mol. 

 lusca, 44. Cuvier's second fa- 

 mily; habits and food, 46. Ana- 

 logy with annulose Vermes, 52. 



Parmophorus, 58. 62. 243. 356. 



Partula, of Ferussac, 179. n. 



Patella, or limpet, 25. 30. 47- 58. 

 357. Nearly stationary, 31. 234. 

 240. Adhesion to rocks, 244. 



Patularia, 287. 381. 



