_Contia_, 205 _Contia modesta_, 205 Coral-Snakes, 32, 34, 35 _Coronella_, 196 _Coronella austriaca_, 197 _Coronella girondica_, 202 _Coronella italica_, 197 Coryphodonts, 58 _Crotalinæ_, 5, 220 Crotalon, 20 _Crotalus_, 21 _cucullatus_ (_Macroprotodon_), 213 Dahl's Whip-Snake, 177 _dahlii_ (_Zamenis_), 177 _Dasypeltinæ_, 5 Defecation, 99 Definition, 1 Deglutition, 98 Dentition, 53 Desert Snakes, 36 Development, 88 Diacranterians, 58 Dicephalous young, 89 Digestion, 99 _dione_ (_Coluber_), 185 Dione Snake, 185 _Dipsadomorphinæ_, 5, 151 Disgorging, 99 Distribution, 118 _Dolichosauria_, 1 _dorsalis_ (_Pelias_), 234 Drinking, 101 _dumfriesiensis_ (_Coluber_), 200 Dwarf Snake, 205 Economic value, 138 Eggs, 85 Egg-eating Snakes, 53, 80 Egg-tooth, 89 _Elachistodontinæ_, 5 _Elaphis cervone_, 182 _Elapinæ_, 5 _Elaps_, 35 _elsneri_ (_Coluber leopardinus_, var.), 193 Embryo, 88 Epiglottis, 79 _Eryx_, 147 _Eryx jaculus_, 147 European Whip-Snake, 170 External characters, 8 Exuviæ, 20 Exuviation, 105 Eyes, 11, 73 False Smooth Snake, 213 _fallax_ (_Tarbophis_), 217 Fangs, 55 Fascination, 104 Fat-bodies, 81 Faunistic works, 130 Feigning death, 104 _fitzingeri_ (_Coronella_), 197 _flavescens_ (_Coluber_), 187 _flavescens_ (_Tropidonotus tessellatus_, var.), 163 Flukes, 112 Flying Snakes, 94 Food, 95 Form, 8 Fossils, 6 Gape, 11 Gastrosteges, 15 _gemonensis_ (_Zamenis_), 170 Genital organs, 82 _girondica_ (_Coronella_), 202 _Glauconiidæ_, 4 Glottis, 79 Grass Snake, 152 Greek Blind Snake, 144 Ground Snakes, 91 Habits, 91 Hæmogregarines, 112 _hagenbecki_ (_Tropidonotus tessellatus_, var.), 162 _halys_ (_Ancistrodon_), 261 Head, 10 Head-shields, 17 Hearing, 74 Heart, 77 _Helagras_, 7 Hemipenes, 82 Hibernation, 105 Hind limbs, 10 _hippocrepis_ (_Zamenis_), 179 Hissing, 102 _Homalopsinæ_, 5 Hood, 9 Horseshoe Whip-Snake, 179 _hugyi_ (_Vipera aspis_, var.), 244 Hybrids, 90 _Hydrophiinæ_, 5 _hydrus_ (_Coluber_), 160 Hyoid apparatus, 42 _iberus_ (_Tarbophis_), 219 _Iguanognathus_, 54 _Ilysiidæ_, 4 Immunity, 66, 71 _incertus_ (_Tropidonotus viperinus_, var.), 167 Incubation, 88 Intelligence, 101 _insignitus_ (_Coluber_), 208 Integument, 8 Intestines, 79 Iris, 37 Isodonts, 58