1 



COLUBBISE SeRPENTS.- 



-REPTILES.- 



-Fi AGIO Serpents. 



49 



Suborder II.— COLUBRINE SERPENTS {Colulrina). 



The Colubrine Serpents are distinguished from the 

 Viperine Serpents by their having strong jaws, both 

 of which are furnished with one or more series of teeth. 

 In some of the species the upper jaw is provided with 

 fangs in front, which are tixed, not hollow, but grooved 

 on the hinder edge, which groove communicates with a 

 gland placed on the side of the face. The head is of 

 moderate size compared with the body, and the crown 

 is often covered with large plates or shields. A great 

 proportion of the species belonging to this extensive 

 and numerous suborder are perfectly harmless, but 

 there are a small number, those having grooved fangs 

 communicating with a poison gland, which are truly 

 venomous, and some among them dangerously so. 

 This suborder contains two sections, which again are 

 divided into several families ; but these, as they differ 

 very much in their habits and method of living, will be 

 best described separately. 



The first section is characterized by the belly being 

 covered with narrow elongated shields or scales, nearly 

 resembling those of the back. 



This section contains two large Families, the Water- 

 serpents {Hydridce) and the Boas (Boidce). 



Family I.— WATER-SERPENTS {Hydridai). 



The Water-serpents {Hydridce), as their name im- 

 ports, are all natives of the salt or fresh water, and 

 are chiefly natives of the Eastern seas. Their nar- 

 row belly-scales are hexagonal or band-like. The 

 nostrils are placed on the upper part of the muzzle, 

 and are furnished with valves. The eyes are situated 

 towards the upper part of the head, and are furnished 

 with a small round pupil. The fangs, wlien present, 

 are of moderate size, and are intermixed with the max- 

 illary teeth. In some the tail is compressed, but in 

 others it is round. Many of these serpents are found 

 exclusively in the sea, in the mouths of rivers, or in 

 salt-water lakes, whilst others live entirely in fresh 

 water. 



THE SEA OR PELAGIC SERPENTS {ffydiina) are 

 not very numerous in species, thirty-two only being 

 described in Dr. Gray's catalogue ; but they are ex- 

 tremely abundant in individuals, and unlike the terres- 

 trial serpents, are always met with in numbers together. 

 So much is this the case, that their appearance serves 

 as a mark to mariners that they are neariug the shore. 

 " On my approach to Bombay," says Dr. Cantor, " I 

 remember the sailors looking out for this phenomenon, 

 until shoals of these animals made their appearance as 

 signs of approaching land." My own experience con- 

 firms this fact, while approaching the mouths of the 

 Hoogly from the Bay of Bengal. Their geographical 

 distribution is entirely limited to the tropical seas, and 

 although the flood-tide carries them as higli up the 

 rivers as the brackish water, yet they are purely 

 pelagic, and as Dr. Cantor well observes, are no more 

 Vol. II. 



found in fresh water than on dry ground; they form 

 par excellence the natatorial type of the order Ophidia. 

 We do not know a very great deal of their habits, but 

 their whole organization proves that these reptiles are 

 destined only to live in the water, and that their organs 

 of locomotion are in no way formed for progressing on 

 land. Their body, in order more easily to cleave the 

 waves, becomes slender towards the two extremities, 

 and much compressed or flattened towards the tail. 

 The belly is narrow and most frequently prolonged 

 into a more or less sharp keel — " a conformation," says 

 Schlegel, " absolutely similar to the keel of a ship." 

 The tail short, but so compressed or flattened as to 

 offer little breadth compared with its extraordinary 

 height, is the chief organ of locomotion ; for by this 

 form, by its vertical position, and its great degree of 

 flexibility laterally, it exercises at once the double 

 function of oar and rudder. The head is small, more 

 or less elongated, conical towards the snout, and almost 

 of the same proportion as the neck ; so that it is well- 

 fitted for overcoming the resistance offered by the water. 

 The eyes, placed laterally, are directed a little upwards 

 and forward, and thus these serpents are enabled to 

 look in all directions, so as to be able to seize their prey 

 or escape the dangers they are incessantly threatened 

 with. The muzzle is elongated into a downward but 

 pointed shield, which closes the mouth and thus pre- 

 vents the water from entering ; and in order to effect 

 respiration without the serpent having need to expose 

 any part of its body out of the water, the nostrils are 

 placed near each other upon the summit of this muzzle, 

 and are provided with a membranous valve which opens 

 to admit the air, and closes to prevent the entrance of 

 the water. A single instant suffices the creature to 

 perform the act of breathing ; which effijcted, it plunges 

 again into the depths of the sea, the water of which 

 cannot enter either by the nostrils or the mouth. The 

 tongue is much less develope_d in the sea than the 

 teiTestrial serpents. As long as they are below the 

 surface of the water they never make use of this organ ; 

 but when they are out of the element, and the animal 

 is blinded, as it were, by the light, it appears of material 

 use as a feeler. The eyes are generally small, and the 

 pupil is always round. The mouth is only of moderate 

 size, and the jaw-bone is sufficiently long to give room, 

 in addition to the fangs, to several small solid teeth. 

 Hence it follows that these sea-snakes cannot erect 

 their fangs so much as the viperine serpents, and in 

 biting their prey, they retain hold of it witli their jaws. 

 The fangs are marked on their hinder edge with a 

 furrow, which communicates with the orifice of the 

 duct which conveys the poison from the gland. They 

 are much smaller than in the colubriue-venomous 

 snakes, and therefore have escaped the observation of 

 many naturalists, who, like Dr. Patrick Russell, deny 

 their existence in several of the species. The other 

 teeth are exceedingly small and numerous. The 



