Hæmolysis, failure of, under exposure of red corpuscles to large doses of venom, 199, 200, 201. “ in venoms, comparative study of, 196. “ power of, possessed by various venoms, 199. Hæmorrhages produced by albuminoid of snake-venom, 162. “ visceral, complicating recovery from bites of _Viperidæ_, 177, 178. Hæmorrhagin in venoms, 187. “ local effects of, not prevented by antineurotoxic serum, 251. “ predominance in venom of _Viperidæ_, 249. Hæmorrhagin, present in some species of _Viperidæ_, 249. “ sensitive to heat, 249. _Hamadryas elaps_, 37. _See also Naja bungarus._ Harlequin or coral snake, 106. _See also Elaps fulvius._ Heart, action of venom on, 184. Heat, comparative effect on venoms of _Colubridæ_, _Hydrophiidæ_ and _Viperidæ_, 161. “ hæmorrhagin sensitive to, 249. “ resistance of hæmolysins of venoms to, 202. “ sole agent in attenuating venom submitted to alternating high frequency currents, 165. Heating destroys toxicity of blood of reptiles, 218. Hedgehog, immunity of, to venom of _Vipera berus_, 226. “ “ “ “ proved experimentally, 226. “ blood of, toxic before heating, antitoxic afterwards, 226. _Heloderma horridum_, 321. “ “ saliva sometimes toxic, sometimes harmless, 323. “ “ venom of, 321, 322. _Hemibungarus_, 39. “ _calligaster_, 40. “ _collaris_, 40. “ _japonicus_, 40. “ _nigrescens_, 40. Henri, V., poison from pedicellariæ prepared by, 273. Herons of Colombia hunt young snakes for food, 227. “ “ probable immunity to snake-venom, 226, 227. Hetero-albumoses, active principle of snake-venom, 164. “ separation from snake-venom, 162, 163. _Heterometrus maurus_, venom of, 279. “ “ “ effect upon sparrows, 279. High frequency currents, alternating, attenuate venom only by thermic action, 165. Hill, Patrick, on duck-billed platypus, 324. Hindus, worship bestowed on _Naja_ by, 38. Holbrook on _Crotalus confluentus_, 125. _Holocanthus_, 305. “ _imperator_, 305. _Homalopsinæ_, sub-family of _Opisthoglypha_, 3. “ geographical distribution, 4. “ aquatic, 4. _Homorelaps_, 57. _Hoplocephalus_, 93. “ _bitorquatus_, 94. “ _bungaroides_ (syn. _H. variegatus_, broad-headed snake), 94. “ _curtus_ (_Notechis scutatus_, tiger-snake), 95. “ “ “ “ “ bite dangerous, 100. “ “ “ “ “ secretion of, 149. “ _stephensii_, 94. Horned rattle-snake, 129. _See also Crotalus cerastes._ Horse, bleeding, aseptically, after vaccination to obtain antivenomous serum, 245, 246. “ immunisation to venom, difficulties attending, 244, 245. Horse, minimal dose of venom lethal for, 176. “ polyvalent serum prepared from, 251. “ red corpuscles of, reasons for choice of, for exposure to action of venom, 196, 197. “ vaccination of, against cobra-venom, 244, 245. Horse-serum must be added to venom to dissolve washed red corpuscles, 197.