Hardenberg—Studies in the Trophi of the Scarabaeidae . 575 
Diplotaxis sordida Say (PL XXXII, Figs 68-69; PL 
XXXIV, Fig. 7). 
Epipharynx. This organ presents a condition similar to 
that found in Serica. It is much reduced, the sense-papillae 
no longer being apparent, hut the lateral row of hairs is still 
present. Its sensory function has evidently been lost. 
Mandibles. These are strongly chitinized, each bearing a 
prominent curved tooth forked at its free end; there is a 
well developed molar. The lacinia is much reduced, its pres¬ 
ence being indicated merely by a whorl of hairs at the base 
of the inner edge of the galea. 
Maxillae (Fig. 68). Except for their short, compact ap¬ 
pearance and greater amount of chitinization, these do not ma¬ 
terially differ from those already described. The teeth of the 
maxillae (here four in number and prominent) are again 
shown to be formed by the galea alone, the lacinia ending in a 
number of strong, stiff hairs. 
Labial structures (Pl. XXXII, Fig. 69; Pl. XXXIV, Fig. 
7). The short transverse mentum has been moved in over the 
sub-mentum, but for so short a distance that it seems to be situ¬ 
ated directly in front of it. The true relative position of these 
sclerites is shown in the diagram. The anterior and poste¬ 
rior plates of the sub-mentum are distinct and nearly equal in 
size, thus differing from the general arrangement which shows 
the posterior plate to be considerably shorter than the anterior. 
Xo sensory structures which would suggest a hypopharynx are 
apparent, but the lateral rows of hairs are present as usual. 
Lachnosterna fusca Froh. (Pl. XXXII, Fig. 70; PL 
XXXIII, Fig. 71). This is the common species. Other 
species were examined but did not show any essential differ¬ 
ences in the shape or structure of their trophi from the species 
here described. 
Epipharynx (Fig. 70). This organ has almost entirely dis¬ 
appeared, the turned-in front and lateral edges of the labrum 
extending nearly over its entire under surface. Whether this 
is the chitinized front and lateral edge of the epipharyngeal 
