72 THE INSECT WORLD. 



those light spiders' webs which float about in autumn, which the 

 French callyf/r de la merge, and we denominate gossamer. 



The fecundity of this fly is very great, for, in the length of a 

 quarter of an inch, the envelope in which these small worms are 

 enclosed contains 2,000 of them. Therefore this ribbon, being two 

 inches and a half long, contains about 20,000 worms. 



The members of the genus Stomoxys, though nearly related to 

 the house-fly, differ from it very much in habits. They live on the 

 blood of animals. The Stomoxys calcitrant is very common in these 

 climates. Its palpi are tawny yellow, antennae black, thorax striped 

 with black, abdomen spotted with brown, and its trunk hard, thin, 

 and long. It deposits its eggs on the carcases of large animals. 



The Golden Fly, Lucilia Casar, lays its eggs on cut-up meat, or 



Fig. 52. Lucilia hominivorax. 



on dead animals. It is only three or four lines in length, of a 

 golden green, with the palpi ferruginous, antennae brown, and feet 

 black. 



A species of this genus, the Lucilia hominivorax, has lately ob- 

 tained a melancholy notoriety. We are indebted to M. Charles 

 Coquerel, surgeon in the French Imperial navy, for the most exact 

 information concerning this dangerous Dipteron, and the revelation 

 of the dangers to which man is liable in certain parts of the globe. 

 But let us first describe the insect, which is very pretty and of 

 brilliant colours. 



Fig. 52, taken from M. Charles Coquerel's Memoir, represents 

 the larva and the perfect insect, as well as the horny mandibles with 

 which the larva is provided. It is rather more than the third of an 

 inch in length, the head is large, downy, and of a golden yellow. 



