gracilis_ bite a Fowl; although, of course, the venom of these Snakes is as virulent as that of a Viper, the animals used for the experiments having died in the course of from one to three hours after they had been wounded. Therefore the greatest caution should be observed in catching or handling these Snakes. The shortness of their fangs and the small quantity of their poisonous fluid, however, will always give a very fair chance of recovery if the proper remedies be applied, should an accident occur. Two or three species of this genus inhabit India, and the rest are found in the Indo-Chinese and Malayan countries, one of the most common of them (_C. intestinalis_) having likewise been received from the Philippines. The _C. nigrescens_ of the mountains of southern India attain to four feet in length, but they are mostly about half of that size, or even smaller. [15] This name being also applied to the harmless _Tortrix scytale_ Lastly, we arrive at THE VIPERINE SNAKES, which have a long, perforated, erectile fang on the maxillary bone, which is extremely short and bears no other teeth. This is described in greater detail subsequently (pp. 93, 94). They are arranged under the two families _Crotalidæ_ and _Viperidæ_. The _Crotalidæ_, or Pit Vipers, have the body robust, the tail of moderate length, or rather short, sometimes prehensile; head broad, sub-triangular, frequently scaly above or imperfectly shielded; a deep pit on the side of the snout, between the eye and nostril; the eye of moderate size, with vertical pupil. They are viviparous. The Pit Vipers are found only in Asia and America; those of the New World surpassing the Asiatic species in size, and therefore they are much more dangerous. Some live in bushes, others on the ground. A rudiment of the curious caudal appendage of the American Rattlesnakes is found as a simple spine-like scale in the Asiatic species, constituting the genus _Halys_. Some have the head covered with scales, having small shields on the edge of the forehead and brows; the cheeks are scaly, and the tail ends in a spine. Of these, the American genus _Craspedocephalus_ and the Asiatic genus _Trimeresurus_ have the subcaudal plates two-rowed to the tip. The genus _Craspedocephalus_ comprises the terrible Fer-de-lance of certain islands in the West Indies, which occurs on the mainland of South America, where four other species are recognised--one of them being found as far north as Mexico.] [Illustration: Fig. 19.--Fer-de-lance (_Trigonocephala mycalæ_)] The Fer-de-lance (_C. lanceolatus_) is met with in Martinique, Santa Lucia, and in the little island of Boquin, near St. Vincent. It attains to a length of nearly six feet; its colour is not always yellow, sometimes it is greyish, and even marbled with brown; the head, which is large, is remarkable for a triangular space, the three angles of which are occupied by the muzzle and the two eyes.