Wasps as Potters. 



425 



Wasps as Potters. 



That the common wasps which come too freely into our houses in late summer 

 are competent paper-makers is a famihar fact to most people. But it is, perhaps, 

 not so well known that all wasps do not follow the same industrial vocation. There 

 are wasps who work only in such plastic material as clay or mud, as well as some 

 who are more masons than potters. 



One of these — the heath potter-wasp ^ — mav sometimes bo found constructint^ 

 its nest on heath-plants. It is a small black 

 and yellow creature differing from the 

 ordinary wasps, among other things, by 

 its hind-bodv being connected to the fore- 

 body by a thin waist as long as the fore- 

 bod v. Its nest takes the form of a low, 

 round-bellied vase with a short neck and 

 turned-out lip, and is made of clay 

 tempered with the wasp's own cement, 

 supplied from the mouth. It consists of 

 a single cell, and before the mouth is 

 closed it is stocked with small caterpillars — 

 which are believed to be stung to keep 

 them quiet — and the wasp's egg. Some- 

 times the vase is placed upon a broader 

 surface than the twigs of a shrub afford, 

 and in that case it loses a little of its grace, 

 the bottom being flattened to give it 

 a better hold. The wasp's egg is not 

 deposited on the living food store, but is 

 suspended by a thread from the roof. 



The wood potter- and the apple 

 potter^ embed small stones into the walls 

 of their nests, so that they have the 

 appearance of having been built up of 

 stones with clay to hold them together. 

 The apple potter occurs in tlic South of 

 France, and Fabre, apparently describing 

 this species, says that the fourteen or 

 sixteen small caterpillars witli which tlie 

 nest is provisioned are only slightly affected bv the stinging (if thev are 

 stung), for they are able to use their jaws and to kick out, as it 

 were, with the hinder part of the body. This power of movement would make 

 them dangerous company for a delicate egg placed among them, or even for a newly 

 hatched grub. Here, then, is the reason why the egg is suspended. Should it be 

 struck by the movement of one of the caterpillars it would swing out of the way 

 like a pendulum ; whilst the newly hatched and tender grub can feed in safety 



'■ Eumenes coarctata. - E; arbustorum. ^ E. pomiformis. 



Plioto by] [E. Slcp, F.L.S. 



Yellow-painted Potter. 



This largo species is a native of Borneo, and well illustrates the 

 general fonu of these potter-wasps, though the present species 

 is remarkable among them for the great length of its " waist." 

 The light marks in the photograph are coloured yellow in the 

 wasp. Four times the natural size. 



