what he calls " muriate of lime," that is, burnt-oyster shells and salt, and declares that a 

 moderate application of this to the base of the tree is a sure preventative ! Such are 

 some of the modes in which the unprincipled try to dupe their ignorant or simple-minded 

 fellow-creatures, who learn too late that they have bought the nostrum or recipe only to 

 be " sold " themselves. 



17. The Oecropia Emperor Caterpillar (Samia [Saturnia] Oecropia, Linn). — Until 

 recently we regarded this gigantic insect as too rare to be classed amongst our foes, but it 

 has lately become so common in many quarters that we fear fruit growers must begin to 

 consider it as an occasional enemy. Few who see for the first time specimens of this and 

 other large native insects are willing to believe that they are really indigenous to Canada, 

 and not importations from some tropical country. Our Emperor Moths, four species of 

 which we have in Canada, are certainly so large in size and so splendid in ornamentation 

 that every beholder must regard them with admiration, and be willing to spare them for 



Pig. 29. 



Colors— Green, Blue, Yellow and Red. 

 their beauty's sake, even if they should prove destructive. They all belong to the same 

 family (Bombycidas) as the noted silk worm, whose productions afford employment to 

 thousands of our fellow- creatures, and subserve the comfort and luxury of a large pro- 

 portion of the human race. From one of our species, the Polyphemus Moth, that feeds 

 upon oak leaves, excellent silk has been obtained by Mr. Trouvelot, of Medford, Mass.; 

 and a coarse but strong fabric his occasionally been manufactured from the cocoons of 

 the species before us. 



The Oecropia Emperor Caterpillar is hatched from a little round egg, flattened above, 

 of a whitish color shaded with brown. The young larva is very tiny at first, but 

 speedily grows until it becomes a perfect giant among caterpillars. When of full 'size it 

 is about four inches long, and presents the appearance of the accompanying illustration 

 (fig. 29). The general color of the body is 'a beautiful pale-green ; the tubercles or 



Pig. 30. 

 Color— Pale-Brownish. 



warts on the top of the first and last two segments are blue, those on the second and 

 third coral : red, and those on the remaining segments yellow ; the smaller tubercles on the 

 sides are blue. As may easily be imagined, the insect presents a very handsome appear- 



