That this difference in the arrangement of the cibarial apparatus points to any distinctive peculiarities of economy has not been ascertained, for the habits of the _Scopulipedes_ greatly resemble those of the _Andrenidæ_; although the habits of one of them, _Anthophora furcata_, are remarkably like those of the foreign genus _Xylocopa_, in its mode of drilling wood. But the _Apidæ_ have cross affinities amongst themselves, thus _Ceratina_ resembles _Heriades_, and some of the _Osmiæ_, in the way in which it nidificates.
The tongues of the _Andrenidæ_ are always shorter, broader, and flatter than those of the _Apidæ_, in which they are always long, cylindrical, and tapering. In the first section of the _Andrenidæ_, the paraglossæ are obtusely terminated at the apex, thence called lacerated, and where they are fringed with brief bristles. The peculiar form of the tongue in this section suggests its being separated into two subsections, that organ being in the first subsection very broad and bilobated, which gives those insects their position in the series by approximating them to the preceding family of the _Diploptera_, or wasps, whose tongues have the same bilobate form, but each lobe in them is furnished with a gland. These tongues, in both cases of the wasps and these bees, may conduce to the building or plastering habits of the insects. The form may aid the wasp and the _Colletes_, the first in the moulding of its hexagonal _papier-mâché_ cells, as it may the second in shaping and embroidering the silk-lined abode of its embryonic progeny. Why _Prosopis_ should have this organization is difficult to conceive, unless it be from an analogy of structure incidentally previously referred to, beyond which any special object has hitherto escaped detection.
In the second section of the _Andrenidæ_, which have the paraglossæ entire and terminating in a point, the tongues all also terminate acutely with a lateral inclination inwards. In the lanceolate-tongued tribe they bulge outwards laterally, although pointed at the apex.
All this subfamily of _Andrenidæ_, excepting only the two genera reputed parasites, viz. _Prosopis_ and _Sphecodes_, are essentially _Scopulipedes_, densely brush-legged, for the conveyance of pollen which they vigorously collect; but from the brevity of their tongues they are restricted to flowers with shallow petals and apparent nectaria, their favourite plants being the abounding _Compositæ_ and _Umbelliferæ_, as well as the _Rosaceæ_, whence they derive the agreeable odours which many of them emit upon being captured.