The FEMALE, or QUEEN differs in the head not being quite so wide as the thorax, in having the _cibarial apparatus_ very much shorter; the _mandibles_ distinctly bidentate, the inner edge of the inner tooth stretching obliquely to the acute inner extremity of the broad apex of the organ; the _labial palpi_ as long as the tongue, with all the joints conterminous, the basal one slightly acuminate, the second linear, the two terminal ones more slender and shorter, the pubescence of the eyes very much longer than in the neuter; the _legs_ more robust and less pilose; the _posterior tibiæ_ convex externally, without the lateral fringes of hair, and their plantæ merely oblong, without the external basal auricle. The ABDOMEN is also considerably relatively longer; and has not the central ventral ridge.
The MALE or DRONE differs from both in being considerably more robust and more completely cylindrical, and very much more densely pubescent; the _compound eyes_ contiguous at the summit, occupying the whole of the vertex, and nearly all the lateral portions of the face, extending below to the articulation of the mandibles, their pubescence much shorter but denser than in the other sex; the _ocelli_ large, and seated at the top of the central portion of the face in a close triangle, a little above the insertion of the antennæ, and in front of the conjunction of the compound eyes, the lateral ones of the triangle being closely contiguous to the upper inner edge of those eyes; the _antennæ_ are more robust and rather longer; the _cibarial apparatus_ very short; the _labial palpi_ about three-fourths the length of the tongue, and the joints conterminous, the _tongue_ robust; the _thorax_ is nearly quadrate; the _legs_ are nearly naked, the four anterior very slender; the _posterior tibiæ_ slightly curved, convex externally; the _posterior plantæ_ more robust, and more convex externally than their tibiæ, they are regularly oblong, and without the basal auricle, the rest of the joints of the tarsi are very short. The ABDOMEN robust, and obtuse at its extremity, but its seventh segment is concealed beneath; the _ventral segments_ concave longitudinally.
1. _mellifica_, Linnæus. (Plate XVI. fig. 4 ♂♀⚲.) _mellifica_, Kirby.