2 BULLETIN 1107, U. S. DEPAKTMENT OF AGRICULTUKE, 



much of these accounts, usually in a jocular vein ; thus " Bugs " Baer 

 proposed to utilize the lead borer in warfare to eat the helmets off 

 the heads of enemy soldiers, who would then catch cold, influenza, 

 and quinsy from standing bareheaded in a damp trench ! With 

 few exceptions the cases recorded are merely accidental and result 

 from the fact that metal blocks the exit of an emerging adult or 

 occurs in the path of a burrowing larva, and they do not constitute 

 direct attacks. In some cases, however, the insects make a direct 

 attack and the resulting injury is serious. 



Insects of many different orders are involved. Beetles, or Coleop- 

 tera, however, are the more common culprits and include the most 

 injurious species. The families represented are Anobiidae (15),^ 

 Anthribidae {30}, Bostrichidae {8, 30, 36, 39, Jpl, if, ^5, 45, .^9, 51, 

 62, 5If), Buprestidae (^7), Bruchidae, Cerambycidae {3, 5, 9, 11, W, 

 21, 25, 36), Curculionidae {30), Dermestidae {Jf, 9, 5^), Lyctidae, 

 Ptinidae {23, 31, 33, 31^), and Tenebrionidae (^i). Insects of other 

 orders which have been recorded as injuring metal are members of 

 the family Cossidae in the Lepidoptera {10, llf,, 30), termites or 

 white ants (Isoptera) {27, 28, 37, Ifi, 50), and the horntail Sirex 

 {6, 17, 18, 36, U, 55) and a wasp in the Hymenoptera {30, 32) . 



Lead is the metal most commonly injured {1, 13, 19, 35, JtS, l^J^, JfS, 

 IfB, Ifi, 53), such varieties of products having been attacked as lead 

 bullets and cartridges {7, 16, 17, 18, 26), lead (and also tin) roofing 

 {3, 5, 9, 10) , lead rain gutters, lead stereotype plates {8) , lead pip- 

 ing for both water and gas {25, ^7, 6"^, 66), lead lining of vats, tanks, 

 and cisterns {15), the sheet-lead protection for beehives, lead cruci- 

 bles, lead fuses {5Ji-), telephone batteries, the lead sheathing of aerial 

 telephone cables {32, 38-1^.3, J^8, Jfi, 51, 52, 51t), high-tension cables, 

 and lead cables in underground wooden-cased conduits {27 , 28, 37, 

 JfO, 50), in Australia, Central America, and the United States. A 

 rather interesting type of injury is that to tubular lead telephone fuses 

 {5Ji). There is an extensive bibliography in many languages. A 

 portion of this literature is cited under " Insects attacking or pene- 

 trating metals," p. 42. Other metals attacked by insects are tin, 

 zinc (actually found in the stomach of the borer) {21), silver-plate 

 service {23, 31, 33, 31^), (quicksilver) lining of mirrors (both in 

 Europe and the United States), and the gilding of chandeliers. 

 Minerals {1^,, 9), shell or horn, other hard substances {22), and in- 

 organic matter {2) are also penetrated by insects. 



The cosmopolitan ptinid beetle Niptus hololeucus Fald. is not only 

 injurious to the quicksilver lining of the backs of mirrors, but also 

 to silver-plate service stored in closets and the gilt on chandeliers. 



* Numbers in parentheses (italics) refer to " Literature cited," p. 42. It should be 

 noted that many records referred to in the text have not been published elsewhere. 



