HYMENOPTEEA ACULEATA. 



INTRODUCTION. 



The Hymenoptera, whicli include the Bees, Wasps, Ants, 

 Ichneumons and Savvflies, as they are familiarly called, may 

 be known by their mandibulate mouths, complete metamor- 

 phoses, their four membranous wings with branching 

 nerves, enclosing a few comparatively large sized cells, or 

 rarely almost nerveless, and by the form of the thorax, 

 all the segments of which are exhibited dorsally. Some 

 forms are wingless. 



The Aculeata may be considered as the highest section of 

 the order, both on account of the ingenuity displayed in 

 their domestic economy and also of their more highly 

 specialized organs. The antenna) as a rule are thirteen 

 jointed in the male and twelve jointed in the female; there 

 are three ocelli in the vertex of the head, and two large 

 lateral compound eyes ; these, however, are sometimes 

 reduced to a single facet, or entirely absent. The abdomen 

 is pedicellate, and the ? is armed with a sting, whoso 

 wound owes its paiufulness to the poison ejected from its 

 poison bag, but even this prominent character is not always 

 present, the tvaQFurmicidw being destitute of a sting. Tiie 

 sting is always retractile, and almost always hidden when 

 withdrawn. In some few genera the J' is winged and the 

 ? apterous, and in one or two exceptional instances the J 

 is apterous, but as a rule both sexes have fully-developed 



