208 OUR HOUSEHOLD INSECTS 



be more or less alike, however dissimilar the perfect insects 

 may be. This law is strikingly exemplified in several of 

 the carrion-feeding flies, whose larvse are sometimes al- 

 most indistinguishable, though the flies are totally unlike. 

 As regards adornment, L. Caesar is really a splendid 

 insect, and so far well deserves a detailed examination. 

 But beauty is only skin-deep, and Ccesar is rather like a 

 whited sepulchre; so that on the whole it is best to 

 avoid too close contact, as its food usually betrays its 

 disgusting nature by imparting more or less of an 

 offensive ddour to the insect. If one should gain 

 entrance to a room and become annoying by its buzzing, 

 and if death be in consequence decreed against it, it 

 is well to remember that it should on no account be 

 crushed ; for if it has come direct from a meal, its 

 digestive tube is pretty sure to be filled with a most 

 foetid fluid, which, when exposed, will not be slow to 

 make its presence disagreeably manifest. And in this 

 connection it should be noted with regard to flies in 

 general, that if they are to be killed by crushing, it is 

 not sufficient to crush the abdomen. The most vital 

 part is the thorax ; here are situated some of the largest 

 parts of the nervous system; serious damage done to 

 these nerve centres is irremediable, and death follows at 

 once. Not so, however, with regard to the head and 

 abdomen : the latter may be crushed, or even removed 

 entirely, without by any means destroying life, and a fly 

 which has received such damage to its abdomen that 

 part of its contents protrude, will still continue to run 

 about as though nothing had happened. The destruc- 

 tion or removal of the head of course puts an end to the 

 action of the organs of sense, unless any such capability 

 is located in the halters, but it by no means deprives the 

 insect of the power of movement. The decapitated head, 



