56 Insect Architecture. 



which, she detached in the progress of excavation. We have 

 recently watched a precisely similar procedure in the instance 

 of a carpenter-bee forming a cell in a wooden post. (J. K.) 

 The only difference was, that the bee did not fly so far away 

 with her fragments of wood as the wasp did ; but she varied 

 the direction of her flight every time : and we could observe 

 that, after dropping, the chip of wood which she had carried 

 off, she did not return in a direct line to her nest, but made 

 a circuit of some extent before wheeling round to go back. 



On observing the proceedings of this carpenter-bee next 

 day, we found her coming in with balls of pollen on her 

 thighs ; and on tracing her from the nest into the adjacent 

 garden, we saw her visiting every flower which was likely to 

 yield her a supply of pollen for her future progeny. This 

 was not all ; we subsequently saw her taking the direction 

 of the clay quarry frequented by the mason-bees, as we have 

 mentioned in page 41, where we recognised her loading her- 

 self with a pellet of clay, and carrying it into her cell in the 

 wooden post. We observed her alternating this labour for 

 several days, at one time carrying clay, and at another 

 pollen ; till at length she completed her task, and closed the 

 entrance with a barricade of clay, to prevent the intrusion of 

 any insectivorous depredator, who might make prey of her 

 young ; or of some prying parasite, who might introduce its 

 own eggs into the nest she had taken so much trouble to 

 construct. 



Some days after it was finished, we cut into the post, and 

 exposed this nest to view. It consisted of six cells of a 

 somewhat square shape, the wood forming the lateral walls ; 

 and each was separated from the one adjacent by a partition 

 of clay, of the thickness of a playing card. The wood was 

 not lined with any extraneous substance, but was worked as 

 smooth as if it had been chiseled by a joiner. There were 

 five cells, arranged in a very singular manner two being 

 almost horizontal, two perpendicular, and one oblique. 



The depth to which the wood was excavated in this in- 

 stance was considerably less than what we have observed in 

 other species which dig perpendicular galleries several inches 



