Sept. 1897.] 
Packard : Transformations of Hymenoptera. 
109 
NOTES ON THE TRANSFORMATIONS OF HIGHER 
HYMENOPTERA—III. 
By A. S. Packard. 
Megachile (possibly centuncularis Linn.'). 
Larva .—Head of the usual proportions, of good size compared with 
the rest of the body. Eye-pieces prominent, full and convex. Towards 
but below the vertex, in between the eye-pieces, is a depressed subcordate 
area, with a subacute depressed tubercle on each side of the median 
line, which may be the antennae; between this area and the clypeus is 
a transverse raised portion; on each side of this ridge and aligned with 
the side of the labrum at its base is a minute corneous tubercle, which 
may be the antennae, though I think not. 
The clypeus is considerably shorter than broad ; its base is a little 
subacutely produced onesidedly, the front edge deeply excavated; the 
surface is not convex and increases in width towards the anterior edge. 
The labrum is broadly subtrapezoidal, twice as broad as long; base 
rounded, semi-circular; anterior edge rather deeply excavated, render¬ 
ing it slightly bilobate. Mandibles slender, not narrowing much towards 
the end, which is unequally bidentate, the inner tooth the smaller- 
they are much broader, stouter and thicker at the end than in Andreni. 
he maxillte are long and slender, acutely pointed at the tip on one 
side, the inner lobe being produced and incurved, while the outer acute 
,° 6 or tu ^ erc ' e ' s m i nu te; this is easily overlooked and more remote 
:rom the other lobe than usual; they are long enough to touch each 
3 ther._ The labium is long, square at the end, corneous; below and 
Posterior to this square corneous or chitinous edge are two minute acute 
■pines on each side of the labium, which are probably the rudimentary 
abial palpi. 3 
The body is thickest towards the posterior end, on the terminal fifth 
>f the body, whereas in Andrena it is thickest at about the middle • 
owards this last fifth the body gradually increases in thickness, and 
hen suddenly rounds off, so that the end is much rounder, more obtuse 
han in Andrena and the larva of Apidte in general. The penultimate 
termte is larger and broader than in Andrena , while the last sternite 
1 smaller; differences readily appreciable. On the whole the larva of 
egachtle resembles that of Bombus more than that of Andrena. 
As regards the head characters, the larval Megachile differs from the 
