64 



THE STUDY OF INSECTS 



With the termites the number of castes is greater than with the social 

 bees, social wasps, and ants; and each caste includes both male and 

 female individuals. The termites differ also from other social insects in 

 that there arc at least two and sometimes three castes whose function 

 is reproduction. The following castes have been found among these 

 insects. 



The first reproductive caste. —At a certain season of the year, late 

 spring or early summer for our most common species in the eastern 

 United States, there can be found in the nests individuals with fully 

 developed wings. These are sexually perfect males and females and 

 constitute what is known as the first reproductive caste. In these the 

 cutieula is black or dark chestnut in color and the eyes arc functional. 

 A little later, these winged individuals leave the nest in a body; some- 

 times clouds of them appear. After flying a greater or less distance they 

 alight on the ground, and then shed their wings. 



At this time the males seek the females and they become associated 

 in pairs. Each of the more fortunate couples that have escaped their 

 enemies, find a suitable place for the beginning of a nest and become 

 the founders of a new colony. Such a pair are commonly known as the 

 king and the queen of the colony; they are also known as the primary 

 royal pair. 



After the nest has been begun, the abdomen of the female becomes 

 greatly enlarged, as a result of the growth of the reproductive organs and 

 their products ; this is greater in certain exotic species than 

 it is in those found in this country. Figure 106 represents 

 in natural size the queen of a species found in India. This 

 queen is comparatively small. In some species the queens 

 become 6 to 8 inches in length ; such queens are incapable 

 of locomotion and rest in a cell with nothing to do but lay 

 eggs. In our native species of termites the queens do not 

 become so large and they do not lose their power of move- 

 ment. 



The second reproductive caste. — There are 

 frequently found in the nests of termites in- 

 dividuals which arc sexually mature but 

 which retain the nymphal form of the body, 

 having short wing-buds which do not develop 

 further. These individuals constitute the 

 second reproductive caste, which is represented 

 by both males and females. The members of 

 this caste are pale in color; their compound 

 eyes are only slightly pigmented; and they FlG . I07 ._ Wo rker 

 TeTme's never leave the nest unless by subterranean of Reticuiitermes 

 tunnels. If a primary king or queen dies, its 

 place is taken by individuals of the second reproductive caste. For this 

 reason, the members of this caste are commonly known as substitute kings 

 and queens or as complemental kings and queens. 



The workers. — If a termite nest be opened at any season of the year 

 there will be found a large number of wingless individuals of a dirty 

 white color, usuallv blind, and of the form represented by Figure 107. 

 These are named the workers, for upon them devolve nearly all of the 

 labors of the colony. A study of the internal anatomy of workers has 



Fie. 106. — ^)ueen 

 white-ant 

 gilvus. 



