ORDER VI. VEIN-WINGED INSECTS. 235 



erally very small, having a curved neck like a hunchback, 

 short antennae, a short, almost triangular hind body, four 

 colorless wings, and a piercer or ovipositor, as thin as a 

 hair, which it most resembles, and by which they make a 

 hole in the soft parts of plants, into which they deposit 

 their eggs. These punctures in the stems, leaves, or buds 

 of plants produce a swelling of the wounded parts, which, 

 by the irritation of the sucking maggots issuing from the 

 eggs, accumulate the sap, and rapidly increase in size, be- 

 coming spongy, or pulpy, or hard within. It is curious, but 

 it is a fact, that each egg grows larger after it has been de- 

 posited in the plant, and sometimes doubles its size before 

 the larva issues from it. 



These excrescences, called galls, are in reality monstros- 

 ities, though they generally present a very fine appearance, 

 so nearly resembling fruits or flowers as to be mistaken for 

 them ; but, instead of seeds, they contain the larvae of in- 

 sects, which feed upon the juices flowing from the wound 

 they have made in the plant. 



The most common protuberances, or galls, are those 

 found on oak-trees, called oak-balls, and those brought from 

 Tripolis, Smyrna, Aleppo, and Mosul, which are extensive- 

 ly known in commerce as a dye-stuff. But we also see 

 green, yellow, or red galls, of the size of grapes, upon sev- 

 eral other kinds of plants. Upon the leaves of willows we 

 often find them resembling warts ; and the branches of the 

 honey-suckle (Azalia nudiflora) are covered with yellowish- 

 green galls of a spongy texture, which, with all the maggots 

 in them, are greedily devoured by many ignorant persons. 

 It is very easy to ascertain whether there are such larvae in 

 a gall or not by cutting it open ; and if the insect has al- 

 ready made its exit there will be a hole left in the gall. 



We have received a number of valuable insects, natives 

 of that State, from Professor D. S. Sheldon, of Iowa Col- 

 lege, at Davenport, and among others two nests of Gall- 



