CONSTITUTION AND DEVELOPMENT OF TERMITES. 29 



*It is hardly practicable to discover Termes iu the act 

 of quitting the egg ; cousequently a large number of examples 

 must be collected, subdivided according to their different 

 stadia, and then compared. 



■^4. The newly hatched larvae are fed on saliva, to which, 

 after some time, is added a clear yellowish vomit, probably 

 largely diluted with saliva ; later still they begin to adopt 

 other articles of diet. 



Examples of which the head is beginning to enlarge must 

 receive but a very small amount of saliva, as is shown by the 

 woody or fsecal colour of the intestinal contents. But those 

 in which the head remains narrow continue for a longer time 

 to receive pure or nearly pure saliva, which is afterwards 

 always administered in some quantity. 



5. If a large number of small and narrow-headed larvse are 

 added to small tube-nests, some without and others containing 

 soldiers, part of those in the former nests are generally found 

 to develop a large head, which is not normally the case in the 

 latter. 



It is clear, therefore, that the colony short of soldiers tends 

 to furnish itself with them, as it does with royal forms. 



But proof is required that the small large-headed larvae 

 really become soldiers. A calculation of the proportionate 

 numbers of the castes in colonies of Calotermites shows that 

 of the soldiers to be very small — at most one in every fifteen 

 or twenty in a very populous nest, or one to every five or six 

 others in a very small colony. Now, in the aforesaid soldier- 

 less nests one large-headed larva appears to every five or six 

 inmates, and in natural nests the small large-headed larvae are 

 very few in proportion to those with a small head. 



All this goes far to furnish the necessary proof. And the 

 matter becomes a certainty if we study the nests of Termes, 

 in which the young, with already differentiated heads, show a 

 large percentage of large-headed forms, in agreement with the 

 fact that a considerable number of workers is developed in 

 addition to the soldiers. 



Evidently, then, the large-headed larvae are des- 



