THE BLUE HUNTRESS 75 



roomy cell. As a final touch the interior is lightly coated with a 

 pale, smooth varnish. The cocoon is finished in two days, after which 

 the larva excretes a mass of waste matter in one end. This accom- 

 plished, it lies quietly awaiting pupation, which follows in eight 

 days. 



The pupa is yellowish white and beautifully folded so that its re- 

 markably long posterior legs do not extend beyond the tip of its 

 abdomen. Its head is armed with four spikes. Upon either side of 

 four of the six abdominal segments there is a "jack," or protruding 

 T-shaped support, and protruding from the opposite sides of the 

 lateral segment is a pair of club-shaped appendages. 



At first I took these strange objects to be the remains of ancestral 

 legs. I thought them inherited rather than acquired characters, but 

 continued observation of the pupa within its cocoon proved the con- 

 trary. They have been acquired in order that the insect's heavy abdo- 

 men may be kept leveled or centered within the cocoon, no matter 

 how it is shaken about or turns of its own accord. 



This is very important to the insect. It is not that the pupa would 

 be injured by contact with the cocoon wall, but rather that the weight 

 of its own abdomen, which is joined to the remainder of its body by a 

 very narrow waist, would have to be borne by the creature's tender 

 legs. In such a case they would become partly crushed and, owing 

 to their great delicacy at this period, would not develop properly. 

 When the legs have become strong and have received their steel-blue 

 pigment, all the supporting appendages shrivel and are completely 

 lost. This takes place three days before the huntress emerges from 

 her cocoon. The supports are inflated with a watery fluid which 



disappears as soon as a breach occurs in the pupal skin. One mav be 



P 



cut off without seriously injuring the wasp, but the removal of all 

 causes deformed legs owing to the abdomen sagging upon them. 



