VE 
Three Genera of Papuan Passalid Coleoptera. 105 
or grooves; the ridges joining the inner tubercles to oneanother and to 
the outer tubercles, form a single, more or less semicireular curve, the 
left arm of which is directed slightly inwards at its extremity, and all 
three sides of the frontal area are more or less concave; the apex of the 
left outer tubercle is bluntly and imperfectly bifid; the anterior angles 
of the head are of not more than 120°, and are very slightly prominent 
in perfeetly fresh specimens; the canthus is more or less rounded or 
almost vertically truncate externally;; the parietal ridges are lightly S-shaped. 
The prothorax is unpunctured above except in the scars; the marginal 
groove is widely incomplete across the middle in front and behind; the 
median groove is well-developed and complete behind, but not in front; 
the posterior angles of the lower side of the prothorax are closely punctured 
and clothed with long hair, the anterior angles being hairless and 
unpunctured. The seutellum is smooth and polished, except in the 
middle of the anterior margin, and in the extreme anterior angles, where 
it is finely punctured and pilose. The Mesothoracic episterna are 
punctured throughout, except in the posterior angles. The mesosternum 
is more or less strongly rugose, except in the angles behind the scars, 
which last are not very well defined. T’he anterior intermediate areas of the 
metasternum are not separated from the lateral areas, and both are very 
hairy and rugose; the posterior intermediate areas are hairless and polished, 
with a few large punctures. The posterior parts of the hind coxae are 
more or less rugulose or finely punctured. The sceulpturing of the anterior 
abdominal sterna is variable; the posterior abdominal sterna are smooth. 
The elytra hairless, and are smooth except in the grooves, of which the 
outer are more strongly punctured than the inner. 
Genus Hyperplesthenus, Kuwert. 
Anterior margin of head more or less distinctly asymmetrical, outer 
tuberele of left side broader than that of right; left outer tubercle 
truncate or double, richt similar or simply pointed; surface of anterior 
part of head level, without any trace of deep excavations on either side. 
Antennae with six lamellae, none of which are very long or slender; the 
first of them not always well developed. Dentition normal, complete and 
well-developed on both mandibles. No primary scars on mentum; 
secondary scars not very large, never reaching posterior margin, their 
posterior ends never widely separated and sometimes united. Anterior 
intermediate and lateral areas of metasternum fused. Type, H. mpar, 
KUWERT. 
