94 SOCIAL LIFE IN THE INSECT WORLD 



the snowy ribbon which runs along the summit of 

 the nest. 



So far, with a little patience, observation is possible 

 and yields a satisfactory result. It becomes impossible 

 in the matter of the complex central zone, where the 

 exits for the larvae are contrived through the double 

 series of overlapping leaves. The little I have been able 

 to learn amounts to this : The end of the abdomen, 

 deeply cleft in a horizontal direction, forms a kind of 

 fork, of which the upper extremity remains almost 

 motionless, while the lower continuously oscillates, pro- 

 ducing the foam and depositing the eggs. The creation 

 of the central zone is certainly the work of the upper 

 extremity. 



It is always to be seen in the continuation of this 

 central zone, in the midst of the fine white foam gathered 

 up by the caudal filaments. The latter delimit the zone, 

 one working on either side, feeling the edges of the belt, 

 and apparently testing it and judging its progress. These 

 two filaments are like two long fingers of exquisite sensi- 

 tiveness, which direct the difficult operation. 



But how are the two series of scales obtained, and the 

 fissures, the gates of exit which they shelter ? I do 

 not know ; I cannot even imagine. I leave tlie end of 

 the problem to others. 



What a wonderful mechanism is this, that has the 

 power to emit and to form, so quickly and methodi- 

 cally, the horny medium of the central kernel, the foam 

 which forms the protective walls, the white creamy foam 

 of the ribbon which runs along the central zone, the 

 eggs, and the fecundating liquid, while at the same time 

 it constructs the overlapping leaves, the imbricated scales, 



