54 APPLE LEAVES, PLANT-LOUSE DESCRIPTIOH. 



appearance, as though they were coated with varnish, tor the 

 purpose of regaling themselves upon this honey dew, or to de- 

 stroy the aphides, diflFerent species of ants, flies, and quite a num- 

 ber of other insects are always found in company with them. Seve- 

 ral of these, and their habits, will be more particularly considered 

 at the close of our account of this species. 



Grouped together, and covering the surface of the twigs and 

 leaves which they infest, these lice are found in all stages of their 

 growth. When newly born they are. almost white, but soon be- 

 come pale dull greenish yellow, which is their prevailing color 

 during the larva, period of their lives, the antennse, the nectaries, 

 the knees and feet being dusky, and sometimes black. The ma- 

 ture females are generally without wings, and their bodies are 

 much broader than in the larva state, being shaped like an egg, 

 the smaller end forward. These, as well as the winged indivi- 

 duals, vary greatly in their colors and marks, as will be seen 

 from the description of this species and its varieties which we 

 here give- 



The WIHOLE89 FEMALES are somewhat less than the tenth of an inch long, and are 

 of a pale yellowish green color, with the head frequently more yellow than the hody . 

 Stripes of a deep green color are commonly present upon the back, or sometimes 

 there is a single stripe in the middle, and transverse ones at each of the sutures or 

 impressed lines between the segments, but these transverse stripes do not extend to 

 the margin upon either side. The eyes are black. The beak, by which it pierces 

 and sucks the juices of the twigs and leaves, the antennae, and the legs, are whit- 

 ish, their tips black or dusky, andthe knees also are commonly dusky. The necta- 

 ries are equal in length to the distance from their bases to the tip of the abdomen, 

 and are dusky or white, with their outer ends black. Protruding from the extremity 

 of the abdomen is a short tail-like appendage, nearly half as long as the nectaries, 

 and of a black color. But in females examined in autumn, at be time of depositing 

 their eggs, thi? appendage was not observed. I hence^ infer it pertains only to those 

 which bear living young. 



The MALES and the winged females appear to be alike in their colors. They mea- 

 sure about 0.12 to the tips of the wings, this being double the length to the tip of 

 the abdomen, or more. The head and thorax are of a coal black color, with the 

 neck commonly grten. The antennae are inserted npon the front part of the head, 

 between the eyes. They are black, slightly tapering towards their tips, scarcely as 

 long as the body, and slightly covered with very fine short hairs. They are seven- 

 jointed, the two basal joints short and thick, almost as broad as long j the third joint 

 is longest of all, apd often shows several slieht equidistant constrictions, dividing it 

 seemingly into several short joints; the fourth and fifth joints are equal, and^ach 



