110 
[Vol. V. 
Journal New York Entomological Society. 
larva of Andrena in its head being a little larger, the antennal tubercles 
being flatter and much less prominent; the eye-pieces less globose and 
spreading less laterally. The clypeus is longer and larger, and the 
front edge deeply excavated, where in Andrena it is square and entire. 
The labrum is narrower, the front edge more excavated, being hardly 
at all so in Andrena. The mandibles are stouter; the maxilla large 
and slender, as is the labrum, which has a broad, thickened, square 
chitinous tip, not present in Andrena , the end of which in Andrena is 
fleshy. 
Fig. 9. Megachile centuncularis. a, larva; b, c, pupa. (Emerton, del .) 
Pupa. _Head broad and flat, subtriangular, the front flattened; 
the supraantennal area broad and flat; seen laterally the head is much 
more vertical than in Bombus , and is more like Apis ; seen from above 
the head is much broader, supraclypeal piece transversely oblong-trian¬ 
gular, thus setting the antennae far apart. Clypeus transverse, broader 
than long, with two curvilinear lateral lobes which are much longer 
and more curved than in Bombus. Labrum square, longer than broad, 
the edges square, the sides contracting slightly towards the anterior 
edge, which is square, not rounded or excavated. Mandibles long, 
stout, thick, not incurved, but rather bent inwards so as to meet just 
in front of the labrum. The eyes are more prominent and farther apart 
than in Bombus. Antennae more rectangularly bent than in Bombus 
owing to the greater width of the head ; the joints are shorter, much 
more convex; only reaching to just beyond the middle of the anterior 
tarsi, whereas in Bombus they reach to the second joint of the posterior 
tarsi. The maxillae reach just beyond the anterior tarsi; neither pair 
of palpi are visible. Paraglossae extending to half-way between tips of 
lingua and the maxillae. The mouth parts are less loosely arranged on 
the breast than in Rhopalum , Pelopeeus and the other fossonal forms. 
