Ants and Caterpillars 115 



hindrance. Sometimes a caterpillar insinuates itself 

 within the cocoon or pupa-case of an ant (popularly 

 called an "ant's egg") , and the workers carry the two 

 about as if they did not notice anything wrong. When 

 there is a migration from the nest, however, the cater- 

 pillars are not designedly flitted. But this does not 

 matter, for, like the family ghost, they cannot be left 

 behind. Little ones cling on to ants' cocoons, or 

 larvae, or clumps of eggs, and are transported to the 

 new nest all unbeknownst. It is a noteworthy fact that 

 the caterpillars appear to be very helpless when they 

 are removed from the ants' nest. 



In the course of time, having eaten many ant- 

 grubs, having grown and moulted according to rule, 

 the caterpillar passes into the quiescent pupa or 

 chrysalid phase. It makes a cocoon of snow-white silk 

 fastened to the nest- wall where it joins the leaf. As 

 there may be a dozen of these cocoons in one ants' 

 nest, they contribute to the strength of the wall and 

 lessen the risk of the two leaves being torn asunder 

 by the wind or by an intruder. It seemed to Dr. Kem- 

 ner that the nests with many cocoons were the most 

 successful. Two of them contained between them 29 

 males, 42 females, and 364 workers ; and this was not 

 near the maximum. 



The moth (Wurthia) is a little white creature that 

 flies by day, without much rapidity or persistence. 

 Another species has its caterpillars living in the nests 

 of the common tailor-ant, but apparently as para- 

 sites rather than as partners. What characterizes the 

 menage of the new species is its active share in spin- 



