LIFE HISTORY OF CARPENTER ANT. 



colonies of Tables I. and II. is 17.5 ; in those of group (#) it is 

 94 ; for the five queens of the four colonies of group-^) it is 271 ; 

 in group (c) it is 402 ; and in group [d) it is 512. Doubtless a 

 large number of the larvae of the last two groups and possibly of 

 one of the colonies of group (6) came from eggs laid by workers. 

 This makes it reasonably evident that eggs are laid by the queen 

 somewhat more rapidly after the first season than during that 

 period when, as shown above, the rate is about two eggs a day. 

 It is also evident that while the queen alone is laying eggs and it 

 is quite probable that the workers do not lay eggs until just previ- 

 ous to the time of the production of winged forms the increase in 

 numbers is slow enough to require several years to reach the 

 two-thousand mark. Without arguing further a point based on 

 uncertain evidence, I feel safe in believing that the colonies of 

 Tables I. and II. are all one year old ; those of group (a) are two 

 years old ; those of group (b) three years old ; of group (c) four 

 years old ; and of group (d) five or more years old. Varying 

 conditions may make the time of development of a colony vary, 

 and so I feel sure that the time required for a colony to reach 

 v maturity is from three to six years. 



As to the life of a colony after it reaches maturity I have the 

 following data : 



1. The average number of winged forms in the colonies of 

 Tables III. and IV. which possessed them was 292. The queen 

 larvae especially must require a great deal more nourishment than 

 worker larvae, and after reaching maturity these forms remain in 

 the nest for three or four months of warm weather and must be 

 fed by the workers. Thus a large portion of the energy of the 

 colony is consumed in rearing and feeding forms which annually 

 leave it. 



2. Colony 1, Table IV., contained a large number of winged 

 forms when collected, and after these winged forms were removed 

 from the colony, the workers laid a large number of eggs some, 

 at least, of which developed into males. Thus it is probable that 

 when colonies once begin to produce winged forms they continue 

 to do so year after year. If this is true, the constant drain thus 

 caused on the energies of the colony might cause it to degenerate 

 in size, if the older workers should die faster than young ones 



