“ _nigricollis_, 62. “ _samarensis_, 36. “ _tripudians_ (Cobra-di-capello), 33-36. “ “ collection of venom from, 156, 360. “ “ marks produced on skin by bite of, 10. “ “ muscular apparatus of head of, 11, 13. “ “ poison-gland of, 11, 13. “ “ var. _cæca_, 35. “ “ “ _fasciata_, 35. “ “ “ _miolepsis_, 36. “ “ “ _sputatrix_, 35. “ “ “ _typica_, 34. _Naseus_, 301. Natter-jack, 318. Neurotoxic and hæmolytic actions of venoms, parallelism between, 255. Neurotoxin, 191, 195. “ essential active substance in venoms, 187, 250. “ highly resistant to heat, 249. “ of scorpion-poison, 278. “ of toad-venom (bufotenin), 320. “ potency of antineurotoxic serum against, 250, 251. “ predominance in venom of _Colubridæ_, 249. “ present in venoms of some species of _Viperidæ_, 249. Neuwied on _Elaps_, 108. New Caledonia, terrestrial poisonous snakes unknown in, 100. New Guinea, poisonous snakes of, 81-100. New Zealand, _Katipo_ found in, 275. “ no poisonous snakes in, 100. Nicolas, J., and Lumière, A., on effect of intense cold on venom, 166. Noc, on action of different venoms, 190, 191. “ bacteriolytic property of venom, with respect to different micro-organisms, 207, 208, 209. “ hæmolytic powers of venoms, 196. “ study of venom of _Ornithorhynchus_, 324. Noguchi, H., on action of aniline colours on venom, 167. “ failure of hæmolysis under large doses of venom, 200, 201. “ and Flexner, cytolytic action of venoms, 206. “ “ “ investigations on toxicity of snakes’ organs, 220. “ “ “ on action of snake-serums on red corpuscles, 219. “ “ Madsen, Th., on ratio between dose of venom and time elapsing till death, 177. Normandy, coast of, _Cottus_ abundant on, 292. _Notechis_, 95. “ _scutatus_ (syn. _Hoplocephalus curtus_, tiger-snake), 95. “ “ “ “ “ bite dangerous, 100. “ “ venom of, dose lethal for rabbit, 175. Oceania, geographical distribution of genera of poisonous snakes (tables), 145. Octopods, poisonous juice exuded by, a means of overpowering prey, 287. _Ogmodon_, 82. “ _vitianus_, 82. Oil beetles, 281. _See also Meloë._ _Ophiogeni_ in Egypt, 228-229. _Ophiophagus_, 37. _See also Naja bungarus._ Ophthalmia, purulent, produced by snake-venom experimentally, 180. “ “ “ venom of species of _Sepedon_, 180. _Opisthoglypha_, group of _Colubridæ_, 3. “ sub-families of, 3. _See also Homalopsinæ_, _Dipsadomorphinæ_, _Elachistodontinæ_. “ “ slightly poisonous and not dangerous to man, 4. _Ornithorhynchus paradoxus_, or _O. anatinus_ (duck-billed platypus), 323. “ “ “ “ “ venom of, 324, 325. “ “ “ “ “ action similar to venoms of _Viperidæ_, 324. “ “ “ “ “ toxicity very slight, 325. Pacific Ocean (Equatorial), _Pterois_ found in, 296. “ “ (Tropical), _Scorpæna diabolus_ found in, 293. “ “ “ _Synanceia brachio_ most commonly found in, 291.