334 NATURAL HISTORY. 



this was the Snake which was worshipped by the natives, and it has a strange literature attached 

 to it, of stories of the most wonderful kind, and it has been confounded with the Anaconda, which 

 forms the next genus of the sub-family. 



Bates once, on an insect-hunting expedition, met a Boa Constrictor face to face. The huge 

 Serpent was coming down a slope, and making the dry twigs crack and fly with its weight, as it 

 moved over them. He knew there was no danger and stood his ground, and the reptile suddenly 

 turned and glided at an accelerated pace down the path. The rapidly-moving and shining body 

 looked like a stream of brown liquid flowing over the thick bed of fallen leaves rather than a Serpent 

 with a skin of varied colours. One morning, after a night of deluging rain at Para, the lamplighter, 

 on his ixmnds to extinguish the lamps, knocked Bates up to show him a Boa Constrictor he had just 

 killed in the street not far off. He had cut it nearly in two with his knife as it was making its way 

 down the sandy street. 



The ability of Snakes to swallow prey, the size of which is greater than that of their heads and 

 necks, might be called in question were it not a very familiar spectacle. Whether the victim has 

 been struck and poisoned, or bitten and enfolded in some twirls of the body, or simply caught 

 in the mouth, sooner or later it is forced within the jaws, and the skin of the head is greatly 

 distended. The crooked shape of the teeth prevents the return of the prey, which is forced 

 farther and farther back, by alternate forward movements of the movable and separable lower jaws, 

 by gapings and general forward movements of the jaws. As the prey gets beyond the middle 

 of the mouth the lower jaws are separated behind from the skull, as much as possible, by the 

 mobility of the quadrate and squamosal bones, and then the extensile gullet receives its morsel. 

 Once past the jaws, the muscular efforts are restricted to the gullet and body. 



A clean skull of a Python, with its bones in their proper place, shows how solid is the brain- 

 case, and how movable are the jaws and their attached bones. On looking at this Snake's skull 

 the pre-maxillary bones are seen in front, and there are teeth in them. This is (with the ex- 

 ception of the genus Tortrix) not the usual arrangement, for teeth are wanting there in other 

 Serpents. 



Then the maxillary bones (on each side) are large, long, arched, and many-toothed, and very 

 different in shape to those of the venomous Snakes. "Within the mouth, and on the palate, is the 

 palatine bone (of each side), also furnished with teeth, whose points look backwards, and the 

 bone is long and is united behind with the pterygoid. Just where they unite a bone passes out 

 to join the maxilla, and this is the transverse bone. The hinder end of the pterygoid bone is in 

 contact with the quadrate and squamosal bones. This last bone (squamosal) is long, and only 

 adheres to the skull by one end, the opposite or outer end being in contact with the quadrate 

 bone. Hence the quadrate bones can be stuck out from the skull by their own and also the length 

 of the squamosal. On looking at the lower jaw the parts at the chin are noticed to be capable 

 of wide separation there; and behind, the mandibles jointed to the quadrate can be forced as 

 widely apart as that bone and the squamosal will let them. Hence the space through which the 

 prey can pass is wide. In the Tortrix (p. 335), which has the exceptional pre-maxillary teeth, the 

 quadrate bone is articulated directly with the skull, the squamosal being rudimentary. So it cannot 

 bolt great morsels. 



The great water-loving Snake of Brazil, about which so many wonderful stories have been 

 told, is the Anaconda,* and it has often been confounded with the Boa Constrictor. Its head is 

 furnished with irregular plates, and that of the Boa is simply scaly. It grows to a great size, 

 however, and a large specimen is usually to be seen in the Zoological Gardens of London. Lying 

 in great coils, with the scales iridescent after it has cast its skin, this Snake may be seen with 

 its prey a couple of ducks in its lively moments. Often, however, it is wonderfully inert, and 

 the birds even rest on it and quack, quack, with full tones. Sooner or later, however, a long head, 

 rather wide behind and with a notable set of teeth, moves upwards out of the coil, and there is a rush 

 forward, and a duck is caught. Soon it disappears down the stretched-out mouth and throat, and the 

 other one follows after an interval. They last long, indeed many months, without food, and in their 

 native home live in and about rivers and swamps, preying on birds and small mammals. 



* Eunectes murinus. 



