SB 

 818 

 C578 

 ENT 



io. 26, Second series. 



united States Department of Agriculture, 



DIVISION OF ENTOMOLOGY. 





THE PEAR SLUG. 



{Erioca)tij>oides liinncinn Retzius.) 



CHARACTP^KISTICS AND HISTOKY. 



The damage to the foHage of the pear, eherry, phini, and alhed trees 

 from the sHmy slug-worm is famiUar io every fruit grower. Two or 

 three generations of these slug-worms, or "slugs," as they are also 

 termed, appear during the summer and frequently in such extraordi- 

 nary numbers, with the later broods, that the leaves of the attacked 

 plants turn brown, die, and fall to the ground in midsummer, and the 

 new growth of foliage Avhich 

 is afterward thrown out is 

 o f t e n si m il arly destroyed . 

 Trees thus denuded are much 

 checked in growth or greatly 

 injured, if not killed. When 

 the slugs are very abundant, 

 as they frequently are in .Tuly 

 during the second brood, the 

 sound of the eating of myri- 

 ads of mouths reseml)les 

 somewhat the falling of tine 

 mist or rain on the leaves, 

 and instead of one or two 

 larva^ at work on a leaf there 

 may be upward of thirty. 

 Under such circumstances a 

 very distinct and disagree- 

 able odor is disseminated by the nudtitudes of slimy slug-like creatures. 



The slug-tly is a small, glossy l)lack insect, considerably less in size 

 than the house flj', measuring only about one-fifth of an inch in length. 

 The wings, which are four in number, are transparent, iridescent, and 

 have a smoky band across the middle, which varies in intensity in dif- 

 ■ ferent specimens. It belongs to the family commonly termed " saw- 

 llies," (TenthredinidaO on account of the saw-like' instrument or 

 ovipositor with which the female insect places its eggs in the leaves or 

 other soft parts of the plant. 



FiiJ. 1.— Pkar SLru: a. adult saw-fly, Icinale: h. larva 

 with slime removed; c, same in normal state: cl. 

 leaves with larvre natural size: a. b.c. much enlarged 



(oritiinnl). 



