FORMS INJURIOUS TO HUMAN INDUSTRIES 



353 



foliage. The Nun {^Psilura inonachd) is a very serious forest pest 

 in Germany, for its caterpillars devour pine-needles and the leaves 

 of hardwood trees in a wholesale manner. The Gipsy Moth 

 i^Ocneria dispar), introduced from Europe into the United States 

 some thirty years ago, has within the last decade proved a veri- 

 table scourge to many trees. Fletcher Osgood makes the follow- 

 ing observations about this particular pest (in Harper s Magazine, 

 1897): — " The careful reckoning of science has demonstrated that 

 the unrestricted caterpillar increase of a single pair of gipsy moths 

 would suffice in eight years to devour the entire vegetation of 

 the United States. In the ordinary course of nature (let Heaven 

 be thanked for it!) such in- 

 crease is never left wholly un- 

 restricted. . . . Since the work 

 [of extermination] began [in 

 Massachusetts], some forty- 

 two millions of trees have 

 been inspected, while the 

 number of the buildings, 

 walls, and fences thus looked 

 over exceeds four hundred 

 thousand. Besides myriads 

 of the gipsy kind destroyed 

 by burning and in other ways, 

 and hosts escaping record in 



the first years of the outbreak, the force employed against the 

 caterpillar has killed directly by hand, to date, about two billions 

 and three millions of these dreadful creatures. The unrecorded 

 destruction will doubtless bring the list of killed to at least 

 some four billions. The results so far have more than justified 

 the necessary outlay." 



The Corn Moth or Corn Wolf {Tinea granella, fig. 1251) is a 

 small granary-pest that does much damage to stored grain. The 

 Clothes-Moths, so destructive to garments of cloth and fur, are 

 closely related. 



The last species to be here mentioned is the Wax Moth 

 {Galleria melloneila), one of the enemies of apiculturalists. The 

 female tries to enter a bee-hive, and, if successful, lays her eggs 

 there. When the caterpillars hatch out they burrow into the 

 combs, and feed upon the wax. 



Fig. 1251.— Corn Moth [Tinea granella). i, Infested 

 grains held together bj' threads of silk; 2, cocoons; 3, larva; 

 4, the same enlarged; 5, chrysalis: 6, the same, enlarged: 

 7, empty chrysalis skin projecting from cocoon ; 8, adult 

 female ; 9, the same, enlarged (actual size in same position 

 indicated at 10). 



