Hardenberg—Studies in the Trophi of the Scarabaeidae . 565 
her of irregular boles of different sizes, wbicb, increasing in 
number at the posterior part, give to the plate a sieve-like ap¬ 
pearance. This feature has been observed only in this one 
species, and its physiological significance is not clear. 
The mandibles are short and more thick and compact, but 
still membranous at the tip; the lacinia is short and the con¬ 
junct vus well developed. 
The labium and labial lobes (Fig. 28). Both lobes are 
membranous, the galea and lacinia fused as usual and but 
sparsely beset with setae. At the junction of the hypopharynx 
the lobes are continued into an elongated area, covered with 
short, blunt, fiat, conical papillae. The hypopharynx itself 
is a thin, membranous plate, convex in front and sparsely 
covered with thin, soft hairs. 
Aphodius granarius Linn. 
This second representative of the genus was taken on account 
of its different food habits. The members of this genus are pre¬ 
vailingly found feeding on cow dung, but A. granarius Linn, 
has become a pest in our granaries, and it was examined to 
see whether such a comparatively slight deviation would show 
any effect on the construction of the mouth-parts. This was 
found to be the case, although the change has not proceeded 
very far and its modification can be directly traced from A . 
fimetarius. 
Epipharynx (Fig. 29). The V-shaped, slightly chitinized 
area described in the preceding species is here flask-shaped 
(a direct modification from the dung-feeding A. fimetarius ), 
more strongly chitinized and sparsely beset with short papillae, 
its posterior border being fringed with a row of sense-cups. 
It does not show the perforations which were found in the 
preceding species. Its anterior tip shows two blade-shaped 
chitinous hairs or teeth. An additional row of blade-shaped 
hairs has appeared on the area between this and the incurved 
lateral margin of the epipharynx. 
Mandibles (Fig 30}. These are shorter and more strong¬ 
ly chitinized than in A. fimetarius. The lacinia has again 
become longer and extends to the tip of the mandible where it 
