a> 
Thorax in winged Insects. 167 
Mr. Kirby has most correctly observed, as well as that it is the evanes- 
cence at last of this small membrane and the junction of the sides of the 
antepectus, or more accurately speaking, the connection of the epimera 
of the prothorax, which forms the singular necks of Xiphydria and 
Fenus. These two Hymenopterous genera, so far from being nearest to 
Coleoptera in structure of the thorax, are the farthest from them, as they 
present no vestige of the prescutum and scutum of the prothorax what- 
ever. 
Mr. Kirby, with his usual acuteness observes, that there is no meso- 
thoracic prescutum, or as he terms it, no prophragma in front of the 
collare, (which, by the way, there ought to be, on the supposition of its 
belonging to the mesothorax,) but one behind it. This is an incontro- 
vertible argument to shew that the collare belongs to the prothorax.* I 
conceive the collare therefore to represent the third piece of the tergum 
of the prothorax in Locusta, which piece is perhaps evanescent in the 
generality of Coleoptera. This view of the matter will satisfactorily ex- 
plain all the difficulties which have been so ably brought together in the 
Introduction to Entomology, and the collare shall hereafter be always 
termed by me the scutellum of the prothorax.t 
But to understand better what precedes, and to have some notion of 
the construction of an Hymenopterous insect, let us take a Polistes.t 
* I know not exactly how Mr. Kirby would argue, and scarcely what he 
alludes to, when he says that the collare is not separated in any way from the 
mesothorax in a“ Neuter Mutilla.” He forgets that in Apterous Hymenoptera 
all the pieces of the thorax are sometimes soldered together into one mass, His 
argument drawn from Xylocopa proves nothing more than that, in this genus 
of Bees, the narrow collare is excessively developed laterally, as in other Hy- 
menoptera it is developed longitudinally. 
4+ According to M. Audouin it is the scutum of the prothorax. 
t My insect is perhaps the most common Wasp in Cuba, where it builds a 
nest of 7 or 8 vertical cells, under the eaves of houses, or any place where it 
may be sheltered from rain. Its nest is composed of the ordinary papyraceous 
substance, and of the form und size of Tap. vi. fig. x1. It is consequently 
rather a solitary wasp, rarely more than three perfect insects being seen 
about a nest, But, on the other hand, in a convenient situation, these 
little nests may be seen studded together in great frequency. As far as 
the vague descriptions of Fabricius will allow me to judge I believe it to be 
