{123}_Sphecius speciosus_ is a member of the Stizinae, a group recognised by some as a distinct sub-family. It makes use, in North America, of Insects of the genus _Cicada_ as food for its young. Burrows in the ground are made by the parent Insect; the egg is deposited on the _Cicada_, and the duration of the feeding-time of the larva is believed to be not more than a week; the pupa is contained in a silken cocoon, with which much earth is incorporated. Riley states that dry earth is essential to the well-being of this Insect, as the _Cicada_ become mouldy if the earth is at all damp. As the _Cicada_ is about twice as heavy as the _Sphecius_ itself, this latter, when about to take the captured burden to the nest, adopts the plan of climbing with it to the top of a tree, or some similar point of vantage, so that during its flight it has to descend with its heavy burden instead of having to rise with it, as would be necessary if the start were made from the ground. SUB-FAM. 7. NYSSONIDES.—_Labrum short; mandibles entire on the outer edge; hind body usually not pedicellate; wing with the marginal cell not appendiculate._ This group has been but little studied, and there is not much knowledge as to the habits of the species. It is admitted to be impossible to define it accurately. It is by some entomologists considered to include _Mellinus_, in which the abdomen is pedicellate (Fig. 48), while others treat that genus as forming a distinct sub-family, Mellinides. Kohl leaves _Mellinus_ unclassified. Gerstaecker has called attention to the fact that many of the Insects in this group have the trochanters of the hind and middle legs divided: the division is, as a rule, not so complete as it usually is in Hymenoptera Parasitica; but it is even more marked in some of these Nyssonides than it is in certain of the parasitic groups.