TWO POTTER WASPS 383 



below the cells. This close scrutiny is observed throughout 

 the labor of building. Nothing is left to itself there is no 

 tolerance of carelessness. Thus the insect's work in all its 

 outward roughness, stands, a lasting monument to its ma- 

 ternal love. 



A single jug or cell is completed in thirty hours. When 

 two-thirds finished, an oily white egg is deposited and fas- 

 tened to its inner wall. The cell is of necessity never finished 

 until the egg is placed, but a few loads of mortar after the 

 laying complete the body of the jug. The flared lip about the 

 entrance is then fashioned from the outside, after which the 

 nursery is ready to be provisioned. 



The caterpillar victims are brought in one by one. 

 There are twenty-two in all, of what I take to be larvae, ei- 

 ther of Tinied or Pyralidina moths. They are pink or green, 

 eight or nine millimeters in length and two millimeters thick, 

 which is just the diameter of the hole left in the jug. 



Storing the cell is a much more leisurely process than 

 building. The wasp visits her nest about once an hour, usu- 

 ally bringing a caterpillar, w r hich she stuffs into the cell with 

 a motion similar to that of a dog nosing earth over a bone. 

 Occasionally she returns empty-handed, and I wonder that 

 it is not oftener. It is winter in the tropics and caterpillars 

 are indeed scarce. One might hunt all day" and perhaps find 

 one, yet the wasp's sense of smell is so highly developed that 

 she readily finds twenty-two for each of her cells. 



The storing finished, the wasp sometimes stops work 

 for an entire day. I have found her thus, with folded wings, 

 quietly resting upon her nest. Indeed, there is no need of 

 hurry now. If the egg within the cell hatches there is plenty 

 of food for the grub, enough to bring it safely to maturity. 

 There are dangers of course. Parasites, or ants would carry 

 off the contents of the open cell, but her presence prevents 

 attack. Later the hole is plugged with a pellet of mud flat- 

 tened out until little trace of the opening remains. The wasp 

 continues to visit her nest even when no more cells are to 



