In France the Common Viper abounds in Jura, Isère, Ardèche, Auvergne, Vendée, and the Forest of Fontainebleau. _Three hundred thousand_ have been killed in twenty-seven years in the Department of Haute-Saône alone. Every year this snake causes the death of some sixty persons. Cow-herds, shepherds, and sportsmen fear it greatly, since it is very dangerous to cattle, sheep, and dogs. II.--GENERAL CLASSIFICATION OF POISONOUS SNAKES. THEIR ANATOMO-PHYSIOLOGICAL CHARACTERS. Poisonous snakes are divided by naturalists into two great Families, the COLUBRIDÆ and VIPERIDÆ, distinguished from each other by certain anatomical characters, and especially by the dentition. The COLUBRIDÆ resemble harmless snakes, which renders them all the more dangerous. They are divided into two groups: OPISTHOGLYPHA (ὄπισθεν, behind; γλυφὴ, a groove) and PROTEROGLYPHA (πρότερον, before; γλυφὴ, a groove). The OPISTHOGLYPHA have the upper jaws furnished in front with smooth or non-grooved teeth, but _behind_ with one or several rows of long, canaliculate teeth. This group includes three _Sub-families_:-- A. The _Homalopsinæ_, having valved nostrils, placed above the snout. B. The _Dipsadomorphinæ_, in which the nostrils are lateral in position, and the dentition is highly developed. C. The _Elachistodontinæ_, which have but rudimentary teeth only on the posterior portion of the maxillary, on the palatine and on the pterygoid bones. Almost all the snakes belonging to these three sub-families are poisonous, but only slightly so. They are not dangerous to man. Their venom merely serves to paralyse their prey before deglutition takes place; it does not afford them an effective means of defence or attack. All the _Homalopsinæ_ are aquatic; they bring forth their young in the water, and are met with commonly in the Indian Ocean, starting from Bombay, and especially in the Bay of Bengal, on the shores of Indo-China and Southern China, from Singapore to Formosa, in the Dutch Indies, in Borneo, the Philippines, New Guinea and the Papuan Archipelago, and as far as the north of Australia. The _Dipsadomorphinæ_ comprise a large number of highly cosmopolitan genera and species, found in all the regions of the earth except the northerly portions of the Northern Hemisphere. None of these reptiles is capable of causing serious casualties among human beings, owing to the peculiarly defective arrangement of their poison-apparatus. I therefore do not think it worth while to linger here over their description. The _Elachistodontinæ_ are of even less importance; at the present time only two species are known, both of small size and confined to Bengal. * * * * *