446 ANNUAL REPORT OF NEW-YORK 



HICKORY. LEAVES. 



their ends, though most of them at that date had become dry and 

 faded to a dark brown color. The leaf is often wrinkled around 

 the gall and has more or less of a fold extending from thence to 

 its outer edge. The insect within, when disturbed, turns its tail 

 upward over its back in a menacing manner, the same as the rove 

 beetles {Staphylinidce) do; and when the point of a needle which 

 has been pressed upon one of these insects is touched to the tip 

 of the tongue, unless my imagination greatly deceives me, it will 

 frequently be found to impart a peculiar acrid biting sensation. 

 This insect is 0.07 long, of a deep black color and highly polished. 

 Its head is narrower than the thorax and nearly square. The 

 third, fourth and fifth joints of the antennae are longer than the 

 others, yellow and slightly transparent; the last joint is shortest 

 and but half as thick as those which precede it. The abdomen 

 is egg-shaped with its tip drawn out into a tube thrice as long as 

 it is thick, with four long bristles at its end, and the abdomen is 

 furnished with bristles at each of its sutures. The wings do not 

 reach the tip of the abdomen. They are white and slightly trans- 

 parent and fringed with black hairs. In its larva state it has a 

 more slender linear form with a dull greenish yellow head, a 

 white thorax with a broad black band anteriorly, a pale red 

 abdomen with a black band at its tip, and w^hitish legs. 



166. Hickory leaf witherer, Phylloxera CarycEfolia, new species. (Ho- 

 moptera. Aphidae.) 



Forming small conical elevations on the upper surface of the 

 leaf, each having an orifice in its summit; a very small black 

 plant-louse with a pale abdomen and legs and smoky wings laid 

 flat upon its back, and having only three veins in addition to the 

 rib. Length 0.06. 



The protuberances formed by this plant-louse are about 0.15 

 high and 0.20 broad at their bases, of a conical form and a dull 

 red or lurid brown color surrounded by a light yellow ring which 

 occupies the substance of the leaf for a short distance around the 

 base of each cone. The apex of the cone is fimbriated or cleft 

 into a number of small teeth which turn outwards, and in the 

 centre between the bases of these teeth is a small orifice leading 

 into a cavity inside of the cone, the walls of which are scarcely 

 thicker than paper, but are very tough like leather. Some leaves 



