368 LOWER VERTEBRATES. 



old ruins, lurking in some cranny for the approach of an unlucky lizard. If irritated, 

 it will dart at its adversary with all the savage vehemence of the most venomous 

 moccasin, and, as it strikes for tlie eyes, its attacks not unfrequently prove dangerous. 



Zamenis includes those Old World snakes, found about the Mediterranean and in 

 India, which generally have the last maxillary tooth enlarged and separated from its 

 fellows by a short interspace. Of the genus Xendaphis but a single species has been 

 described ; a few specimens, some measuring six feet in length, have been captured in 

 the East Indies. Philodryas viridissimus, a most beautiful example of the Colubridas, 

 and connecting them with the Dendrophidfe, inhabits Brazil, where, because of its 

 slender body and beautiful green color, it has received the name of emerald whip- 

 snake. It lives on young birds, and on such small prey as it may capture while 

 meandering among the branches of the trojjical forests. 



The members of the family Dexdeophid.e, or tree-snakes, are found sporting amid 

 the luxuriant foliage of tropical America, Asia, and to a less extent, Africa and Aus- 

 tralia. To adapt them for an arboreal life, the body and tail is greatly elongated, and 

 each ventral scute is usually provided with a jiair of keels by which the animal can 

 the more firmly grasp the smooth branches. The genus Dendro2}his includes a large 

 number of species, which are frequently adorned with the brightest colors, of which 

 green is often the prevailing tint. The head, which is distinct from the neck, is nar- 

 row, long, and depressed, the snout being very prominent. Two species, representing 

 two genera, are natives of Mexico, Jjeptophis viexicnnus, and Oxybelis ceiieus, which 

 latter species, though of small diameter, reaches a length of four feet. The Boom- 

 Slange, Uticephalus cajyensis, of South Africa, presents so much variation in its mark- 

 ing that several species have been described by those unprovided with a sufficient 

 number of specimens. Though the inhabitants of South Africa consider this form to 

 be poisonous, on dissection no venom glands have lieen found, though the teeth are 

 covered with a slimy secretion, which maybe possessed of irritating qualities. Allied 

 to Bucephalus is Ahcehdla Uocercus, one of the most beautiful of tree-snakes, inhabiting 

 Borneo, where the native children are said to often make a pet of it, the harmless 

 reptile coiling around their arms and bodies without their evincing the slightest alarm 

 and naught but pleasure. In its native haunts the animal is most active, leajiing from 

 branch to branch of the highest trees, and directing its lithe form with lightning 

 celerity towards any unfortunate lizard or beetle which it may chance to espy. Liv- 

 ing also in Borneo, as well as on neighboring islands, is the larger Goniosoma oxy- 

 cephalum, which reaches a length of eighty-two inches. It is said to be a most active 

 and ferocious animal, defending itself, when attacked, with great energy. 



The tree-snakes proper are included in the genus DendropMs, and are character- 

 ized by having an obtuse snout, equal teeth, and smooth vertebral scales. Dendro- 

 pMs picta is the most common East Indian form, and, like Bucephalus, it is liable to 

 great variation in color. D. punctidata is a beautiful animal inhabiting Australia, 

 and growing to a length of five or six feet. It is of an olive-green color above, and 

 pale yellow below ; the shades of color, however, appear to depend on surroundings, 

 as specimens in captivity are never so brilliant as those seen gliding along the grass- 

 land, or swinging from branch to branch of the lofty trees. The neai-ness to the time 

 of exuviation has also considerable to do with the coloring; specimens just after the 

 old epidermis is shed being very brilliant. The eye of this form is large ; the teeth 

 small and of uniform size, and the dorsal row of scales considerably exceeds in size 

 those of the scales of the body. A loreal, a scale generally characteristic of this as 



