TERMITES. 



681 



worker grade and the affairs of the community are carried on by 

 the soldiers and active larvae. This species lives in passages, 

 excavated in dead or decaying trees ; they build up barriers with 

 their own ejecta and line the galleries with secretions from 

 their salivary glands or from the anterior end of the alimentary 

 canal. The colony is small, with some hundreds of individuals, 

 but rarely numbering a thousand. The royal couple move 

 about and their progeny increases slowly ; two years may see 

 a family of fifty, and when some 

 five hundred have been produced 

 the queen diminishes the output. 

 The winged insects take more than 

 a year before they swarm, after 

 which they pair off and start new 

 colonies. 



From what has been said it is 

 evident that the continuation of a 

 colony of termites depends on the 

 well-being of the king and queen or 

 of a small number of queens. To 

 diminish the risk which is concen- 

 trated on a few individuals, the 

 termites manage to keep certain of 

 the larval forms (Fig. 430) in such a 

 condition that should anything happen to the royal pair, they 

 may -by proper attention probably a change of diet become 

 reproductively active. The activity of the reproductive functions 

 takes place in an insect still in a larval stage.* Before it sets in 

 these individuals are known as u reserve " or " complementary ' 

 kings and queens ; after it has been brought into use they 

 are known as " substitution ' royalties. In the case of 

 T. lucifugus the colony is mainly carried on by such forms. The 

 reserve or complementary monarchs are however not derived 

 from stages immediately preceding the final or normal adult 

 instar, but from some earlier larval stage, and by no means 

 always from insects in the same instar. 



The termites, inhabiting their enormous nests, keep the in- 

 terior of their dwelling scrupulously clean. They not only eat 



FIG. 430. Larvae of Calotermes 

 rugosits (after F. Muller). /' wing- 

 like appendages of the prothorax ; 

 /" rudiment of the fore-wing ; /"' 

 rudiment of tin- hind-wing. 



* Cf. Amblystoma. The larval stages with active reproductive powers 

 are sometimes called " neotenic." 



