HEMIPTERA. 203 



time; and he informs me that the same destructive depreda- 

 tions have been observed in all the adjacent region. On the 

 23d of July, I saw these insects on the trees, some already- 

 provided with wings, and others advancing towards maturity. 

 The young ones were of a dull orange yellow color. They 

 were short, and were obtuse behind, and had little wing-scales 

 on the sides of their bodies. The perfect, or winged individu- 

 als, were about one tenth of an inch long from the forehead 

 to the tips of the closed wings. The front of the head was 

 notched in the middle. The eyes were large and prominent. 

 The head and thorax were brownish orange, and the hind body 

 greenish. Their four ample wings were colorless and trans- 

 parent, and were marked with a few dark veins. The body of 

 the female is pointed at the end, and inclines to a reddish hue. 

 The pear-tree, in Europe, is subject to the attacks of a similar 

 insect, called Psylla Pi/ri, the pear-tree Psylla. The European 

 species is said to vary in color at different ages, and in different 

 seasons of the year, being of a dull crimson color, shaded 

 with black in the spring, when it comes forth to lay its eggs. 

 Not having seen any of our pear-tree Psijllce in their spring 

 dress, I cannot say whether they agree with those of Europe 

 in being of the same crimson color at this season of the year. 

 As, however, they do correspond very nearly in other respects 

 to the descriptions given of the European species, and have 

 precisely the same destructive habits, and as they were first 

 detected upon imported pear-trees, I apprehend that they were 

 introduced from abroad, and that they will prove to be the 

 same species as the European Psylla Pyri. The following 

 particulars, abridged from KoUar's " Treatise," if confirmed by 

 future observations, will serve to complete the history of the 

 American insect. The European pear-tree Psylla comes forth 

 from its winter retreat, provided with wings, as soon as the 

 buds of fruit trees begin to expand. After pairing, the female 

 lays her eggs in great numbers near each other on the young 

 leaves and blossoms, or on the newly-formed fruit and shoots. 

 The eggs are oblong, yellowish, and look somewhat like grains 

 of pollen. The young insects hatched therefrom resemble 

 wingless plant-lice, and are of a dark yellow color. They 



