336 NATURAL HISTORY. 



a fold in the throat which permits of the extension of the skin. The eyes are very small. These 

 Uropeltidse, having such remarkable Saurian affinities, live in the East Indies and in Ceylon, and it 

 is necessary to dig to a depth of four feet to obtain them. 



SUB-ORDER TYPHLOPIDJE. THE BLIND SNAKES. 



These are small Snakes, and are by no means readily distinguished by an ordinary observer from 

 the Sheltopusiks, Blind-worms, Amphisbaense, and other Lacertilia with Snake-like bodies, and more or 

 less imperfect limbs. They lead a life like that of the burrowing Anguis (p. 297), their bodies are 

 vermiform, cylindrical, and rigid, and there are the relics of hind limbs in the form of small rod- 

 shaped bones. They are not blind, for the eyes are present, although small, but they are covered by the 

 ocular and pre-ocular shields, which are more or less transparent. The teeth are found in the 

 upper and lower jaw according to the genera. These Snakes are allied to the Lizards in that they 



have the long axes of the palatine bones transverse, and there is no 

 transverse bone as in the Snakes proper. Moreover, the pterygoids 

 are not connected with the quadrate bone. They have not the power of 

 enlarging their narrow mouth, and they feed on small worms and insects. 

 They are divided into two families : in one, the Catodontes, there are teeth 

 only on the lower jaw, which is shorter than the upper ; * in the other, 

 SIDE VIEW OF HEAD OF the Epanodontes, the teeth are on the upper jaw, and the extremity of 



BLIND SNAKE. (After Gun- .. , . 1 J Ml/ 1 1 ,. -i 1 



ther.) the muzzle is truncate and covered with large scales, the nostrils being 



situated laterally on the anterior margin. Typldops lumbricalis, of the 



Antilles, is the type. Some other small Blind Snakes, with the rudiments of hind extremities 

 hidden beneath the skin, and a small eye covered by the ocular and pre-ocular shields, are in- 

 habitants of almost every part of the Tropics, and about eight species occur in British India, 

 and the most remarkable is Typhlops tennis. 



The Australian Blind Snake is Typldops rilpelli, and it lives in ants'-nests. 



In concluding this natural history of the Serpents it is necessary to make a few remarks on 

 some of their more important peculiarities of structure. The tongue, that long, rapidly-moving 

 organ, which is evidently often used as a feeler, as well as a menacing agent, is slender, cylin- 

 drical, and forked. It is lodged in a membranous sheath, the opening of which is situated near the 

 anterior part of the mouth, and the reptile can protrude it from the mouth to nearly its whole 

 length. The esophagus and stomach form a continuous tube of variable length, and it is difficult to 

 determine where one ends and the other begins. But the stomach is strengthened by muscular layers, 

 and the folds in it are more numerous. It is short in relation to the length of the reptile, and any 

 large prey is retained partly in the oasophagus. There are two parts, one of which, in front, is the 

 " sack," and the other the pyloric end, and this is more or less bent on the other. It has no folds, and 

 has to deal with the more or less digested food. The intestine is much looped in the True Serpents, 

 and this seems to refer to the movement of the reptile on its belly, and the possibility of this acting 

 perniciously on a simple elongated gut. That of the Water Snakes is simpler. They all have a lobed 

 liver, a spleen, and a pancreas. 



They have a complicated lymphatic system, and there are lymphatic hearts situated just above 

 the origin of the tail, and they are large in the Python. A diminished and atrophied condition of 

 one of the lungs has already been noticed in some Lizards, and it is found in the Serpents, and has 

 to do with the room which great prey requires when swallowed. It is not necessary to refer to 

 the circulation, except to notice that the ventricular septum is incomplete. The great nervous 

 centre has the two hemispheres broader than long, the olfactory bulb is frequently of large size, and 

 the corpus striatum is smaller than in the Lizards. The cerebellum is very small and flat, and 

 the so-called bigeminal tubercles are well developed. 



In the ear there is no proper tympanic cavity, and the handle of the auditory ossicle is embedded 

 amongst the flesh, so that its extremity only touches the skin, close behind the articulation of 

 the jaw. 



* Stenostoma niyricans, an African species, is the example. 



