Social- Wasps. 87 



themselves ; one species using sound wood for the pur- 

 pose, another that which has become decayed. This they 

 scrape by means of their jaws from posts, rails, gates, hurdles, 

 &c., in which act it becomes mixed with some peculiar fluid 

 with which they are provided ; it then possesses nearly the 

 same properties as the pulp from which paper is made, but is 

 of firmer consistence. This is gathered in a small lump 

 under the chest, to which it adheres, and in that way is 

 carried to the nest. 



** The operators having, after the exhibition of a considerable 

 amount of fickleness in the choice, fixed upon a suitable place 

 for commencing, or recommencing operations for these re- 

 marks have reference to a nest already somewhat advanced 

 in the building place themselves along the edge of a yet 

 unfinished piece, then walking slowly backward, spread the 

 material as they go, along this edge, where it forms a thick 

 streak ; they then go forward to the point at which they 

 began to spread the composition, again marching slowly 

 backward, press this streak between their jaws, which acts as 

 a pair of pincers, thus thinning it out throughout its whole 

 length. They then go forward a second time, pressing it 

 still thinner, and then a third, and so on, until they have 

 rendered it sufficiently thin. Before this is accomplished, 

 the operators have generally to go five or six times over their 

 work. They do not return to the same spot with their next 

 burden, but seek a fresh one, and thus allow the work they 

 recently executed to become dry and firm, previous to making 

 further additions to it. Possibly the material first ' used 

 up ' was from wood of a dark colour ; the next may be from 

 light- coloured wood, and the next from that of an inter- 

 mediate colour ; and this it is which gives so much beauty to 

 the coverings of the nests of these insects. 



" Yespa crabro and V. vulgaris are the only species which use 

 decayed wood or touchwood in the fabrication of their nests ; 

 the other species employ sound wood, varied occasionally 

 by sound vegetable fibre obtained from plants of different 

 kinds. 



" From the upper combs in a nest, workers are produced ; 



