166 MESSES. C. HOENE AND P. SMITH ON HTMENOPTEEA 



Fam. EUMENIDiE. 

 EuMENES CONICA, Fabr. (Plate XX. figs. 2 & 2 a.) 



As I bred many of these insects, I had ample opportunity of watching them. They 

 place their nests on the walls of houses, but prefer wood, such as door-frames; while 

 sometimes they make series of cells of great length, one such series often extending 

 more than one foot. 



One pair of insects will construct twelve or thirteen cells, and it does not take an 

 entire day to complete one of them; yet I have often thought I could detect more than 

 one pair engaged in one place, but at different ends of the structure, which, when com- 

 l^leted, contained perhaps twenty-four cells. 



It should be remembered that the insect avails itself of the wall or beam for the back 

 of its cell, which is made extremely thin, the clay which is carried beneath the mouth 

 being beautifully fine and well kneaded. Hence it is extremely diflacult to detach their 

 cells without breaking them. The cells are high and vaulted, and at the mouth they 

 have a protruding rim, which projects outward and curves slightly downward. Ten or 

 twelve green caterpillars are stored in each cell, which is carefully closed with mud. 



This insect, like Peloposus madraspatanus, seems very proud of its work, and, before 

 leaving for fresh material, runs about approvingly and thoroughly inspects its perform- 

 ance. If disturbed it flies off, and does not attack you as do the Vespidse. 



The imago generally emerges about five weeks after the cell has been closed ; and, 

 owing to the thinness of the walls, which are easily pierced, it is much attacked by 

 parasites. Thus out of one group of five cells, only two specimens of JEumenes were 

 hatched. Of these parasites I shall speak afterwards. 



In life the Eumenes is much brighter in colour than it becomes after death, so that 

 no idea of its beauty when at work can be readily formed from the specimens. It was 

 from one of the cells of this species that I took nine caterpillars, eight of them being 

 blacTc Geometers, and only one green one ; so that it is clear the insect had, contrary to 

 custom, met with a brood of another colour which suited it quite as well as the green, 

 which it generally uses. 



Eumenes esuriens, Fabr. (Plate XX. figs. 6 & 6cx.) 

 This beautiful insect builds its cells about doors and windows, on the posts ; and fig. 6 

 may be held to be a typical structure. As, however, I bred them from cells of different 

 forms, there can be no doubt that they vary their style with the site. The cells are high, 

 very spherical, and placed generally irregularly. Green caterpillars (chiefly Geometers) 

 are stowed away, whilst one often finds the cells in the possession of a Golden Wasp 

 {Chrysis), a parasite. The mouth of the cell resembles that of the other species in 

 having a recurved lip, this being characteristic of this group. The reason why so many 

 cells are empty after the escape of the perfect insect is, that the ants come in troops 



