110 'Insect Architecture. 



The shape and size of the nest are exceedingly variable, 

 but it is almost invariably longer than wide, and is fixed to a 

 branch or some similar object. Sometimes it attains con- 

 siderable dimensions, and has been known to measure a full 

 yard in length. Yet, however large it may be, there is only 

 a single comb, which is set upon the side of the nest next the 

 branch, and, in consequence, has almost all its cells placed in 

 a horizontal direction. In the illustration, the right-hand 

 figure represents the external appearance of the nest, and the 

 central figure shows the manner in which the single comb is 

 set upon the branch. The nest which occupies the left hand 

 of the illustration is made by a species of Polybia, and is here 

 given in order to show a remarkable example of similarity in 

 the mode of building adopted by two. different insects. In 

 the one case, however, the cells are all fastened by their bases 

 to the branch, but in the other the cells are attached to one 

 common base which is prolonged into a footstalk. 



There have been lately discovered some very remarkable 

 social nests. Specimens of both these nests may be seen in 

 the entomological department of the museum at Oxford. 



The first is formed very much like a rather flattened 

 Florence flask, and is hung by the neck from the branch of a 

 tree. It is made of a strong, parchment -like substance, 

 formed by innumerable silken threads woven and matted 

 together into a kind of felt. When it was cut open a most 

 singular sight was exhibited. Nearly the whole of the 

 interior was covered with the pupae of some butterfly, all 

 hanging by their tails, and many of them suspended to a 

 twig which projected downwards into the nest. Although 

 the nest is barely eight inches in length, a great proportion 

 of which is taken up by the neck, about one hundred pupae 

 were found in it. At the bottom of the nest is a small and 

 nearly circular aperture, through which the insects could 

 make their way as soon as they escaped from the pupal 

 envelope, and before their wings became extended and 

 hardened. 



The butterfly which makes this singular nest is a native of 

 Mexico, and is named Euclieira socialis. The colour of its 



