INSECTA 623 



this point. Oblique or side illumination shows the play 

 of colours on the scale to the greatest advantage. 



To the genus Ptinus belongs a small beetle known as 

 the Death-watch, rig. 281. This and the species Anobium 

 are found in our houses, doing much in- 

 jury whilst in the larval state. The eggs 

 are often deposited near some crack in a 

 piece of furniture, or on the binding of an 

 old book. As the larva? are hatched, they 

 begin to eat their way into any furniture 

 on which they may have been deposited ; 

 and, having attained a sufficient depth, 

 they undergo transformation, and return, The p^th-watch 

 by other passages, as perfect beetles. In Atropus, magnified. 

 furniture attacked by them, small round holes, about 

 the size of the head of a pin, may be seen, and to these 

 holes the term worm-eaten has been applied ; and the 

 noise, made by the insect striking its head against the 

 wood, has given rise to the name of Death-watch. The 

 larva is called a Book- worm when it attacks books ; old 

 books and those seldom used, are often found bored 

 through by it. Kirby and Spence mention, that in one 

 case twenty-seven folio volumes were eaten through, in a 

 straight line, by this insect. The beetle is very small, and 

 almost black. The head is particularly small ; and from 

 the prominence of the thorax, looks as 

 if it were covered with a hood. The 

 Anobium puniceum, fig. 282, attacks 

 dried objects of natural history, and all 

 kinds of bread and biscuits, particularly 

 sailors' biscuits, in which maggots fre- 

 quently abound. In collections of in- 

 sects, it first consumes the interior ; 

 when the larva assails birds, it is gene- 

 rally the feet that it devours first ; and L 

 in plants, the stem or woody part. The Fi& 282.— Anobium pu- 



, *■ . ' ,-, , .. u \ ., , , niceum, magnified. 



larva is a small white maggot, the body 

 of which is wrinkled, and consists of several segments 

 covered with fine hairs ; its jaws are strong and horny, 

 and of a dark brown. The body is white, and so trans- 

 parent, that the internal organs of the insect can be seen 



