574 Wisconsin Academy of Sciences, Arts, and Letters . 
ditions. The hypopharyngeal fulcrum is still present and 
fairly well developed. 
Macrodactylus subspinosus Fab. (Pl. XXXII, Figs. 64 
67). In this insect the trophi are less strongly chitinized and 
show an approach to those of the pollen-eating beetles (Eu¬ 
phoria et al.). This was to be expected, as this species lives 
on the soft petals of flowers and has no need of strongly chiti¬ 
nized mouth-parts. 
Epipharynx (Fig. 64). This shows a better development 
than in the preceding species; the sensory area is larger, the 
sense-cups are more numerous, and the arrangement of the 
hairs and sense-pits reminds us of that in Hoplia trifasciata. 
Mandibles (Fig. 65). These are less chitinized, both galea 
and molar having undergone a reduction. The lacinia <is 
again enlarged and much broader, giving the whole mandible 
a more leaf-like aspect. A remnant of the conjunctivus is 
here suggested, there being a slight difference in structure in 
that part of the base of the mandible which adjoins the molar. 
Maxillae (Fig. 66). These are noteworthy in that they show 
that the teeth with which the maxillae are armed in Serica 
and the preceding species are really formed by the galea, and 
that the lacinia does not take part in their formation. Galea 
and lacinia are here separate and distinct, the former ending 
in five strong teeth, the latter having a small tuft of hairs at 
its end. 
Labial structures (Fig. 67). The mentum, which with its 
appendages has been pushed in over the sub-mentum, is com¬ 
paratively broad, narrowing toward the posterior end. It beais 
on its ventral side the short three-segmented palpi, while on 
its dorsal surface is a small transverse piece which is corne¬ 
ous and projects dorsally. This I consider to be the remnant 
of, the fused inner lobes of the labium. Laterad of this we 
again find the usual rows of long hairs converging posteriorly. 
At the place where we should naturally expect the hypophar- 
ynx to be, there are only a few sense-pits. 
