FAMILY POISONOUS SNAKES. 



105 



TYPHLOPS. This genus has great resemblance in the disposition of its 

 scales to the Blind Worms, Angues. Their general form is very similar 

 to Earth Worms ; they live in the ground, and feed on ants and termites, 

 which is perhaps the reason of their eyes being protected with so thick skin. 



POISONOUS SNAKES. 



The Venomous Serpents are divided into two sections, viz., those having 

 poisonous isolated fangs, and those with fangs accompanied by several 

 maxillary teeth. The latter have a close resemblance in the construction 

 of their jaws to those of the Unpoisonous Snakes, their upper jaw-bone 

 being large, long, and furnished with a row of strong curved teeth ; while 

 in the former the jaw-bone is short, thick, and armed with one or two very 

 large curved hollow teeth. In the most deadly venom-snakes the poison- 

 fangs acquire a large size, and are more strongly curved backwards than 

 the ordinary teeth. 



ILLUSTRATIVE EXAMPLES. 



PLATE 6. 

 Family FANGED POISONOUS SNAKES. 



Genera. 



Species. 



Common Name. 



Crotulus - - - - Horridus - - - - Banded Rattle-snake. 



Vipera ----- Berus. 



Cerastes - Hasselquistii. 



Naja ----- Lutescens - - - Yellowish-hooded Snake. 



Tnmeresurus - - Microcephalus. 



family FANGLESS POISONOUS SNAKES. 



Pelamis vel Pelamides - - Bicolor - - - Bicoloured Sea Serpent. 

 Pseudo-boa seu Bongarus - Fasciatus. 



Family NAKED SNAKES; Nudes. 



This family is composed of but one genus, the Ccecilians ; whose smooth 

 and viscid skin appearing naked, has suggested the title by which they are 



designated. 



Coecilia - - - - Glutinosa. 

 Other Genera of these Families : Hydrophis, Trigonocephalus. 



CHARACTERS OF THE GENERA. 



1. CROTALUS (Gr. KporaXov, a rattle). Single transverse scaly plates 

 along the belly and tail ; extremity of latter furnished with a rattle, composed 

 of numerous rings of horn received within, and moveable upon each other ; 

 poison-fangs on each side of the upper jaw. 



2. VIPERA (Gr. "nnrw, I hurt). Head depressed, vertex in some covered 

 with scuta, in others scaly; no depression before the eyes; body scaly 

 above ; abdominal scuta single, subcaudal in pairs ; solid teeth in the palatine 

 and inferior maxillary bones ; in the superior maxillary, poison-teeth only. 



3. CERASTES. Nearly the same as Vipera. 



4. NAJA (from the Indian word Nagou, a poisonous Snake). Poison-fangs 

 in the upper jaws, enclosed in a doubling of the gums, when at rest ; mouth 

 extensible ; nose truncated, back of the head wide ; head covered with large 

 scales; neck opposite the space included between the sixth and twelfth 

 abdominal scales dilatable into a kind of hood supported by the ribs ; beneath 

 the tail a double row of scales. 



5. TRIMERESURUS (Gr. rpi/u'pijc, divided into three parts, and ovpa, a tail). 

 Upper jaw furnished with poison-fangs ; abdominal scuta entire ; caudal 

 scuta near the vent in pairs, towards the middle the same but larger, and 

 near the tip smaller pairs. 



1. PELAMIS (Gr. TTT/XOC, mud). Body long, slightly cylindrical, and 

 terminating in a flattened, obtuse tail ; body, head, and tail covered with 

 small scales ; tongue short and thick ; vent single and without hooks. 



2. PSEUDOBOA (Gr. i^eujj/c, spurious, and Boa, a kind of Snake). Body 

 covered with hexagonal scales ; ventral and caudal plates simple ; poison- 

 fangs short and prominent, when the mouth is closed received into cavities 

 in the lower jaw. 



1. CCECILIA (Lat. axcus, blind). Body long and cylindrical, covered 

 with a finely-granulated skin ; head depressed ; eyes very small ; teeth 

 small, pointed, and numerous ; no poison-fangs. 



FANGED, FANGLESS, AND NAKED SNAKES. DESCRIPTION OF THE SPECIES. 



CROTALUS Rattle Snake. Of this venomous genus fortunately there are 

 but few species, and these are all provided with a kind of rattle, whence 

 they derive their name, the noise of which gives warning of their proximity 

 to those who may accidentally come within their haunts. The body of the 

 Rattle Snake is of a lengthened cylindrical form, diminishing in size toward* 

 the tail, and covered above with numerous carinated scales, whilst the belly 

 is defended with narrow, single, transverse scales, extending from below the 

 neck to the tip of the tail. The head is large and fiat, of a triangular sliape, 

 and covered from between the edges with scales similar to those on the back, 

 whilst those on the muzzle and those which cover the eyes are larger, and 

 in the form of plates : the mouth is wide, and the upper lip pierced by a 

 little groove behind each nostril ; in the upper jaw on each side is placed 

 the poison-fang, which is curved and sharp, about an inch in length, with 

 a hole about the eighth of an inch from its point, through which the poison 

 is ejected ; the poison-fangs are contained in a sheath, and thrown out with 

 considerable violence at the pleasure of the Snake. The poison of the Rattle 

 Snake is very virulent, particularly if the Snake be in health. 



An account has been given, by an American writer, of a farmer, who, 

 whilst mowing, accidentally trod upon a Rattle Snake, which bit him through 

 his boot, and he died very soon after. A few days subsequently one of his 

 sons put on the same boots, was seized with the same symptoms on pulling 

 them off in the evening, and died on the following day. His effects were 

 disposed of by sale, and a neighbour bought the boots ; after wearing them 

 he also was attacked with the same symptoms, but under medical treatment 

 recovered. In consequence of this, it was thought right to examine the 

 boots carefully, and in one of them was found the fangs of the Snake with ' 

 the poison-bags still adhering to them, and it appeared that these three per- 

 sons had scratched themselves in pulling off the boots. Catesby states that 

 the danger more materially depends on the severity of the bite than on any 

 other cause ; that he has known persons bitten survive many hours, but where 

 the fang had pierced an artery or vein, inevitable death ensued in less than 

 two minutes. 



The power of fascination ascribed to the Rattle Snake is now much ques- 

 tioned ; the opinion of Dr. Barton, of Philadelphia, that the story of fascination 

 has arisen from the fears and cries of birds and other animals, in protection 

 of their nests and young, being pretty generally adopted. 



Rattle Snakes are viviparous ; they are affected by music ; are eaten by 

 the Indians, who watch them when asleep, and then pinning down their neck 

 with a forked stick, irritate them to bite a piece of leather, which they 

 forcibly pull from them till they have jerked out the poison-bags, and having 

 done that, they skin the animals, and cook them as we do Eels. They are 

 all natives of America, and have been subdivided into two subgenera, from 

 the head being covered either with scales, like those on the back, or with 

 scuta or broad plates. 



Plate 6 contains an illustration of the Banded Rattle Snake (C. Horridus), 

 a member of the first division. It measures from five to six feet in length ; 

 general colour greyish, with a number of black lozenge-shaped spots, edged 

 with yellowish-white on the back ; tip of the tail black ; belly yellowish- 

 white and not spotted ; rings of the rattle from one to thirteen. 



VIPERA Viper. These animals are all oviparous ; and it is presumed by 

 Mr. Bell, that the membrane of the egg is broken in the act of parturition, for 

 he observes, " I have examined several in which the young have appeared 

 ready to be excluded, and have always found the investing membrane entire, 

 although so thin and soft as to be torn by the slightest force." They are 

 all poisonous, and some more highly so than other. In this country we 

 fortunately possess only one. During winter they retire to holes, and become 

 torpid, but as warm weather returns, they revive, shed their coats, and 

 during the heat of summer are very active, and most dangerous. 



The Common Viper (V. Berus), figured on Plate 6, measures from eighteen 

 inches to two feet in length, of which the tail is less than one-ninth. Its 

 colours vary considerably, so that several species have been described, which 

 have proved to be merely varieties of the one under consideration. The 



