156 INSECTS INJURIOUS TO THE PEAR. 



No. 78. — The Iridescent Serica. 



Serica tricolor Say. 



This beetle is said to have proved very injurious to pear- 

 trees in New Jersey by devouring the leaves. It is of an 

 oval form, about one-fifth of an inch long, of a dull bluish- 

 black color, and clothed with long, fine, silky hairs, especially 

 on the thorax ; it is represented in Fig. 163. 

 Fig. 163. 'pj^|g insect has the same habit of dropping to the 

 ground when the trees are jarred or shaken as the 

 goldsmith-beetle (No. 77), and if it proves at any 

 time troublesome it may be collected in this way and 

 destroyed. It is not known how or where the larva of this 

 species lives, but it probably dwells under ground and feeds 

 on the roots of plants. 



No. 79. — The Pear-tree Aphis. 



An undetermined species of aphis sometimes attacks the 

 leaves of the pear-tree early in June, causing them to twist 

 and curl up very much. In tlie pupa state these insects are 

 active, with the wings partly developed. They are then 

 green, with a row of brownish dots along the back, which 

 are smaller on the anterior segments and larger on the middle 

 ones ; there are also some streaks of the same color along 

 each side. The wings are enclosed in cases on the sides 

 about half the length of the body ; body plump ; honey-tubes 

 pale whitish, tipped with black ; feet pale whitish. All the 

 specimens seen at this time have partly or fully developed 

 wings. 



In the perfect winged specimens the head is black ; thorax 

 black above, greenish l^low ; body brownish black above, 

 green on the sides and beneath, with a few blackish dots ; 

 antennae brownish black. When the insect escapes from the 

 pupa state, the empty pupa skin is left attached to the under 

 surface of the curled leaves. 



