PSEUDONEUROPTERA. 77 



short wings which extend only two-thirds the length of the ab- 

 domen. 



In England certain stone-flies are much used by anglers. One, 

 Chloroperla viridis, is well known under the name " Yellow Sally,"' 

 and a species of Nemoura is called the " Willow-fly.' 



Family IV. TERMITID.E.* ,, 



(Termites, or White-ants^ 



The Termites, or white-ants, are social insects, which live in large 



societies, consisting of several distinct forms of individuals. They 



are chiefly tropical ; but there is one species which is commonly dis- 



, tributed over the United States east of the Rocky Mountains ; and 



several others occur farther west. 



These insects can be easily recognized by the pale color of the 

 greater number of individuals of which a colony is composed, by the 

 fact of their living in large ant-like colonies, and by the form of the 

 abdomen, which is broadly joined to the thorax instead of being 

 pedunculate as in the ants. 



The Termites are commonly called white-ants on account of 

 their color and of a resemblance in form and habits to the true ants. 

 These resemblances, however, are only very general. In structure 

 the Termites and ants are widely separated ; as the former are 

 among the lowest of winged insects, while the latter stand near the 

 head of the series. In habits there is little more in common than 

 that both are social, and the fact that in each the function of repro- 

 duction is restricted to a few individuals, while the greater number 

 differ in form from the sexually mature males and females, and are 

 specially adapted to the performance of the labors of the com- 

 munity. 



This development of distinct castes for the performance of spe- 

 cial functions is carried much farther among the Termites than it is 

 among the ants and other social Hymenoptera. In the latter there 

 are only three forms : males, females or queens, and workers, which 

 are imperfectly developed females. With the Termites there are 

 nearly three times as many. 



If a white-ants' nest be opened at any season of the year there 

 will be found a large number of individuals of a dirty-white color, 



* TermUidae: 7'ermes, a white-ant. 



