AUSTEALTAN SNAKES. 27 



FAMILY OF ROCK S^AKY.S-FYTIIONII>.R 



The Australian Rock Snakes are ratlaer more numerous in genera 

 than other non-venomous tribes inhabiting this country, and, excepting the 

 Boli/evia multicar'mata* six more or less distinct species of them have been 

 observed. 



The largest snakes belong to this family, and individuals of great 

 length occur, some measuring as much as ten feet, and perhaps more. 



The body is muscular, more or less compressed in young individuals ; 

 tail prehensile, with a pair of spurs representing rudimentary limbs at its 

 root, which are often hidden beneath the scales. The head is elongate, 

 flat, and covered with many irregular small plates ; if any regular 

 plates are present, they never reach further than to between the eyes. The 

 scales are smooth, and the rows they form around the body far more 

 numerous than in any other tribe of Ophidians inhabiting Australia, so 

 that by the large number of scales alone their harmless nature may be 

 ascertained. The pupil is vertical, but dilates at night or in the dark ; in 

 fact, all our Pythons are Night Snakes, and when observed in the day-time 

 moving about it is generally because they have been disturbed. The teeth 

 are numerous in both jaws ; they feed on the smaller mammals, birds, &c., 

 which they kill by pressure ; they lay eggs, and incubate them. 



Pythons are found on the Indian Continent and the islands of the 

 Archipelago, in Africa and Australia. The American Boas form a different 

 family. 



The way in which these snakes attack their prey is very simple. 

 CoUed on the branch of a tree, the reptile moves only the head and part of 

 the body, advancing and retreating — in fact, measuring its distance with 

 head and neck bent into the form of a horizontal S. When pretty sure of 

 its aim, the snake darts forward with open jaws, fastens upon the victim, 

 and in an instant brings it within a loop formed by a portion of the body, 

 which gradually tightens tiU the prey is suffocated. In this position the 

 snake will remain for twenty minutes or half an hour, holding the body of 

 the animal tightly ; it then gradually uncoils, and, if inclined to feed, 

 begins the process of swallowing with the head. 



* 'I'his species is mentioned erroneously as inhabiting the neighboiu'hood of Port Jackson. 



