129 



well-known species. The nest differs from that of every species of this genus with 

 which I am acquainted : all the nests which I have seen are globular, or sometimes 

 flask-shaped, each consisting of a single cell. The only British species, Eumenes 

 coarclata, constructs a small nearly globular nest of mud, forming a single cell; it 

 constructs a separate nest for each individual: these nests I have found iu Hampshire, 

 attached to twigs of heath. The nest, however, of Eumenes tinctor is very different; 

 it is pear-shaped and constructed of mud, being three inches and a half long and nine 

 inches in diameter at its widest part, but is considerably narrower at the top and 

 obtuse at the bottom. This nest appears to have been constructed amongst rank grass 

 or reeds, having blades passing through it; by these means it was doubtless held in 

 a suspended position: there are twelve outlets, showing that a number of individuals 

 have issued from it. 



"4. EaphigasterGuineensis, 5'awM. This is the Zelhus Guineensis of Fabricius, 

 Syst. Piez, 283, 2. The nest of this species consists of a number of exposed cells 

 attached to each other, a slender twig forming the base of attachment; the cells 

 are about an inch in length, and of a very thin papery texture ; the number in the 

 nest exhibited is seventeen ; there are eight unfinished cells : what may be an average 

 number in finished nests has not been ascertained, but either it must be considerable, 

 or the number of nests very great, as the insect is extremely abundant. 



"5. Mischocyttarus labiatus, Sams. Zethuslabiatus of Fabricius, Si/st. Piez. 284, 

 6. This nest is very similar to the preceding in form and mode of attachment; it is 

 placed upon a slender twig; the texture is, however, very different, being apparently 

 constructed of decayed wood : it is very fragile, and breaks with a slight touch, simi- 

 lar to the cells of Vespa vulgaris: the cells are of a circular form. 



" 6. Icaria guttatipennis, Sauss. This wasp is described in Man. des Guepes So- 

 ciales, p. 40, 19, pi. 5, fig. 8. Its cells are exposed in the same manner as those of a 

 Polistes, and are hexagonal. This nest is of the greatest interest, as exhibiting a 

 direct contradiction to the theory that all cells are originally constructed of a cylindri- 

 cal form, and that the hexagonal form is attributable to the fact of the insects work- 

 ing in concert in opposite cells, the space between the cells gradually falling into 

 straight sides, thus forming regular hexagons ; consequently the outer surface of the 

 exterior cells will be rounded. The nest of thiS insect exhibits a series of regular hex- 

 agons, the outer cells being as sharply angulated as the inner ones. 



"7. Eumenes This is a small mud nest, of globular form, about the size 



of a cherry, adapted to contain a single larva; it is attached to the back of a leaf. 



" 8. Odynerus This wasp constructs a nest in hollow reeds, lining and 



separating the cells with red sandy loam, in the same manner as the Odynerus laevi- 

 pes of Britain. 



" 9. Pelopa;us chalybeus. Smith, Cat. Foss. Hi/m. Part 2. The nest of this insect 

 is especially interesting. The species of the genus Pelopteus are popularly known as 

 mud-daubers in America. They differ in the mode of constructing their nests ; some 

 species appear to place single cells in different situations; others construct a number 

 close together, and even one cell upon another. P. chalybeus differs from all the spe- 

 cies whose habits have been recorded ; it constructs single cells of cow-dung, attach- 

 ing them to stems of grass. From one of the nests I extracted a perfect specimen of 

 the insect. 



" 10. Chalicodoma cfelocera. This is the Megachile caelocera of my ' Catalogue 



