1896] MICROSCOPICAL JOURNAL. 47 



Figure 1 is a greatly enlarged view of the end of this 

 labium or lip, with the projecting setas which constitute 

 the sucking tube, and this as may be seen consists of four 

 pieces, the two outer ones being curved nearly to the 

 form of hooks, while the two intermediate pieces are 

 straight and terminate in extremely sharp points. 



The two exterior pieces serve as hooks, or anchors 

 which being inserted into the bark or leaf of a tree fur- 

 nish a leverage for forcing in the two interior lancets, 

 which together form a sucking tube through which the 

 juices of plants, on which these insects are said to live 

 may be drawn. 



Figure 2 represents a transverse section through the 

 abium, as at the dotted line d, in fig. 1, and shows in 

 what curious manner the four set«, which are grooved 

 on the inner side, form a tube when held together by the 

 Imuscular labium, which is wrapped closely around them. 

 Sections of these four pieces as they appear when separ- 

 ated, are shown below in the same figure. Each of these 

 has a minute tube through it, which would hardly seem 

 to be of much use, considering the size of the insect, and 

 its food requirements, for the main tube in the center is 

 scarcely more than the one-thousandth of an inch in 

 diameter, while the outer diameter of the whole four 

 pieces constituting the stylet is exactly one-three- 

 hundredth of an inch, or about the same as that of a rather 

 fine human hair. 



How much injury might possibly be done by these in- 

 sects during their short lives, by sucking the juices of 

 plants through such minute tubes is, notwithstanding 

 their great numbers, a question, but I have never been 

 able to discover one in the act of feeding, although I 

 watched great numbers of them, on cherry, pear and 

 other trees, and was equally unable to discover any in- 

 jury to the fruit or foliage of such trees later in the sea- 



