76 THE INSECT WOELD. 



The inhabitants of the Zambesi can, therefore, have no domestic 

 animal but the goat. When herds of cattle driven by travellers 

 or dealers are obliged to cross these regions, they only move them 

 during the bright nights of the cool season, and are careful to 

 smear them with dung mixed with milk ; the Tsetse fly having 

 an intense antipathy to the dung of animals, besides being in this 

 season rendered dormant by the lowness of the temperature. It 

 is only by such precautions that they are able to get through 

 this dangerous stage of their journey. 



The large blue meat-fly, the familiar representative of the 

 genus Callipkora, is known to all by its brilliant blue and white 

 reflecting abdomen. This fly, which is common everywhere, is 

 the Calliphora vomitoria on which Reaumur has made many 

 beautiful observations, which we will make known to our 

 readers. 



If we shut up a blue meat-fly in a glass vase, as Reaumur did, 

 and place near the insect a piece of fresh meat, before half a day 

 is passed, the fly will have deposited its eggs thereon one 

 after the other, in irregular heaps, of various sizes. The whole of 

 these heaps consists of about two hundred eggs, which are of an 

 iridescent white colour, and four or five times as long as they are 

 broad. In less than twenty-four hours after the egg is laid the 

 larva is hatched. It is no sooner born than it thinks of feeding, 

 and buries itself in the meat, with the aid of the hooks and lancets 

 with which it is provided. 



These worms do not appear to discharge any solid excrement, 

 but they produce a sticky liquid which 

 keeps the meat in a moist state and 

 hastens its putrefaction. The larvae eat 

 voraciously and always ; so much so, 

 that in four or five days they arrive at 

 their full growth. They then take no 

 Fig. 54.~Eggs of the Meat-fly. more nourishment until they are trans- 

 formed into flies. They are now about 

 to assume the pupa state. In this condition it is no longer neces- 



de 1'Afrique australe, et voyages a travers le continent Sainte-Paul de Loanda a 

 I'Embouchure du Zambeze, de 1840 a 1846, traduit de 1'anglais." In 8vo. Paris, 

 1859. Pages 93 95. ED.) 



