578 Wisconsin Academy of Sciences, Arts, and Letters . 
Cyclocephala immaculata Oliv. (Pl. XXXIII, Pigs. 77-79; 
Pl. XXXIV, Pig. 10). 
Epipharynx (Pig. 77). This is short, entirely corneous, 
and does not show any sensory structures. The usual lateral 
rows of hairs enclosing a V-shaped area are still present. The 
epipharynx is thus very much reduced and apparently func¬ 
tionless. 
Mandibles (Pig. 78). These show a considerable differ¬ 
ence in form from those in the preceding species of this group. 
The molar is small and not strongly chitinized; the galea is 
narrow and does not as usual end in a tooth, but is flat and 
thin at its extremity. This gives the whole mandible a some¬ 
what elongated appearance. The lacinia is prominent and 
thickly covered on its inner edge with moderately long hairs. 
Maxillae (Pig. 79). These are elongated and slender. The 
galea is somewhat quadrangular in shape, covered with numer¬ 
ous thin, long hairs, and its distal edge bears small, irregular 
teeth. The cardo is no longer triangular as in the preceding 
species of this group, but has become elongated and club- 
shaped. 
Labial structures (Pl. XXXIV, Pig. 10). The posterior 
plate of the sub-mentum is short and transverse; the anterior 
plate is long; its lateral edges are slightly convex and converge 
anteriorly. The mentum is pushed in for a considerable dis¬ 
tance over the sub-mentum, is broader than its distal part, and 
has its lateral edges converging posteriorly. 
Ligyrus gibbosus De G. (PL XXXIII, Pigs. 80-82; Pl. 
XXXIV, Pig. 11). 
Epipharynx (Pig. 80). At first sight this organ ap¬ 
pears totally different from those already described for 
other species. Its anterior part is entirely corneous, the 
chitinization extending backward for some distance along 
the median line. Instead of the usual lateral row of hairs 
converging posteriorly, we find that in this species the entire 
lateral portion of the chitinous area is covered with moderately 
long, pointed hairs which show no definite arrangement. The 
