OP THE STATE ENTOMOLOGIST. 



97 



THE PINE-LEAF SCALE-INSECT — Ilijtilaspis pinifolice (Fitch.) 



(Subord. HoMOPTKRA, Fam. Coccid.*;.) 



f^'^- ^^-^ There are several undescribed 



bark-lice — some of them quite 

 .interesting — which attack our 

 forest and shade trees, and espe- 

 cially our evergreens ; but for 

 want of time to make proper 

 descriptions and figures, they 

 must be passed overfor the pres- 

 ent. An exception is made of 

 the Pine-leaf Scale, because, 

 first, it is the most common and 

 injurious of them all ; and, sec- 

 ondly, by coupling its history 

 with that of the Oyster-shell spe- 

 cies of the Apple, much unne- 

 cessary repetition is avoided ; for 

 notwithstanding the last named 

 normally inhabits the bark, while that under consideration is confined 

 to the leaves, the two insects belong to the same genus, and have pre- 

 cisely similar modes of development. 



Many persons, who justly esteem the White Pine one of the most 

 valuable of our ornamental, shade, and timber trees, and who, in 

 adorning their homes, have duly planted of it, have doubtless been 

 sorely vexed at seeing their favorites gradually overspread with what 

 is by some called the "white malady." This malady is an affection of 

 the leaves, and though not many are aware of its true nature, they 

 readily perceive that the unfortunate trees wear an unnaturally yel- 

 low, or brown, and sickly aspect, and in some cases, after languishing 

 a few years, die outright. 



The leaves of such trees present the appearance of figure 35, «, 

 being covered with innumerable elongate white bodies, and looking 

 very much as though finely and profusely sprinkled with molten wax 

 or paraffine. Careful examination will show these bodies to be the 

 scales of the insect in question, and though when few in number they 

 are mostly found in the groove of the leaf, which partially screens 

 them, yet when abundant they cover the more salient sides, and give 

 the tree a whitened look, 1 have never found this insect in injurious 

 abundance, except on young trees; and according to Dr. Fitch, it 

 is never met with upon the trees growing wild in our forests. It has 

 proved quite troublesome to the young trees around St. Louis, and 

 especially along the line of the Missouri Pacific Railroad. It was 



E.R— 7 



