430 



LOWER VERTEBRATES. 



safety, on being disturbed, in the crevices, where it so clings on to the irregularities 

 of the sides as to make its capture almost an impossibility. If it be dislodged, how- 

 ever, it flies at its enemy with the utmost fury, not infrequently compelling it to retire. 

 The reptile's food consists of frogs, crabs, and small quadrupeds, for which it is often 

 seen lying in wait beside some spring or brook of running water. The superstitious 

 natives, who greatly dread the animal from a mistaken belief that it is poisonous, 



Fig. 247. — VaraJius nilot'ums, mouitor. 



noting this semi-aquatic habit, have become possessed of the idea that the animal is 

 sacred, and, if injured, has the power, by way of revenge, of producing drought. 



The monitor, T^ niloticus, has the elongated tail with a double-edged keel above, 

 and the teeth rounded. As its name implies, this animal is an inhabitant of the !N"ile, 

 in which it spends most of its time, seldom going on shore except to search for 

 crocodile's eggs, of which it destroys large numbers. It is, in fact, a most important 

 animal, as it keeps these furious monsters from multiplying to an undue extent, by wa- 

 ging a constant war against them, not only by breaking open their nests and eating the 



