474 



Marvels of Insect Life, 



and a proportionately large head. The only parts of the Insect which can be said 

 to have a thick deposit of brown chitin are the jaws, which are made firm for biting. 

 These take the form of a pair of stout, short shears, with the opposing edges well 

 toothed. The head is adorned with a pair of long and very fine antennas of many 

 minute joints, which are kept perpetually waving. The fore-body appears to 

 consist of two segments only, but this is due to the second and third having been 

 united. As usual, it supports the three pairs of legs, which are remarkable for the 

 stoutness of the thighs, though the shanks are very slender and end in the three- 



jointed foot and its pair of hooked claws, 

 only slightly narrower than the rear part. 

 Insect does not suffer from any shortage 

 why it should, for it appears to feed upon 

 from old books to household stores 



The hind-body is oval, the fore part 



and giving the impression that the 



of food. There really is no reason 



any animal or vegetable substances 



in the cupboards, or the dried 



Photo by. 



Brown J. ace-wing. 



" specimens " of the naturalist, be thev plants. Insects, or larger animal remains. 



The book- 

 louse retains the 

 same form through- 

 out life. As there 

 is no development 

 of wings, and no 

 alteration of the 

 mouth-parts, there 

 is no metamor- 

 phosis. The only 

 changes- — other 

 than of size — that 

 come to it is a 

 darkening of the 

 skin to a brownish 

 grey as maturity 

 is reached, an in- 

 crease in the num- 

 ber of joints of the antenna.% and the development of simple e\-es in addition to the 

 compound pair. 



There is one point in the natural history of this Insect that must be mentioned. 

 All have heard of the " death-watch " that fills the superstitious with alarms. 

 The ticking of the death-watch proper is the nuptial signalling — bv a code older 

 than the Morse — of the little wood-boring beetle ^ that drills pinholes in our most 

 prized old furniture. The book-louse — which is also known as tlie lesser death- 

 w^atch — makes similar sounds, though less loud. More than two hundred years 

 ago, the Rev. W. Derham brought this fact to the notice of the Royal Society ; but 

 since his day there have not been wanting those who, because their ears may not 

 have been rightly attuned to sounds so delicate, have denied his statements on the 

 ground that the book-louse is too soft to produce a noise by rapping its head or 

 other part of it against anything. But in s])ite of these denials, tlic hook-louse docs lick! 



1 Anobiuni hilriatum. 



The wingsof the green lace-wing flies and the brown lace-wings are formed on the same plan. Although 

 when in use they appear tons so flimsy, it will be seen from this enlarged view that the meshes of 

 the lace are well knit. .\ strengthening rib extends along near th;- front edge, and a brancli from it 

 runs parallel with the inner margin. 



