MITYS. 97 
Group TENEBRIONIDES. 
This group will include the “Ccelometopides” and the “Group I.” of the “Téné- 
brionides vrais” of Lacordaire; the Group I. (Upes) and part of “Group II.” 
(Tenebrionides) of the Tribe “Tenebrionini” of Leconte and Horn (Class. Col. N. A. 
1883, p. 376). 
Comparatively few of the species, or even of the genera, of the numerous tropical 
species of this group have been worked out as yet, though many of these are represented 
in collections, and are sometimes to be seen labelled as species of Vyctobates, Iphthimus, 
or Upis, genera with which they have little to do. Several genera not yet detected in 
our country are found in North America, two of which, Upis and Iphthimus, also occur 
in Europe. 
Though unwilling to make the numerous additional genera described here, it seems 
to me far preferable to do so than to place these species under genera which, if we 
included them, it would be almost impossible to characterize. Most of the species, 
with the exception, perhaps, of those of the first two or three genera, are found beneath 
bark. 
MITYS. 
Form of Polyplewrus. Mentum (Tab. V. fig. 7 a) trilobed, small, narrow, scarcely transverse, inflexed on each 
side, longitudinally convex in the middle; inner lobe of the maxille with a short curved tooth at apex 
(Tab. V. fig. 7); last joint of the maxillary palpi subsecuriform ; antenne (as in P. nitidus, Lec.) long 
and thin, last joints not transverse; epistoma broad, slightly rounded and not emarginate in front ; 
sides of the front swollen and slightly divergent ; the front flattened between the eyes; prothorax as in 
P. nitidus ; scutellum small, transversely triangular; elytra rather short, inflated or slightly swollen, 
convex, smooth, or with fine punctured strie ; epipleure wide and narrowing gradually from the base, 
obsolete behind, and not reaching the apex; legs as in P. nitidus :—the tibiew curved inwardly, and clothed 
with short matted hair (more distinctly in the male) on the inner side at their rounded apices (the spurs. 
almost obsolete), the tarsi long and densely clothed with hair beneath; prosternum narrow, deflexed 
behind, the apex produced and rounded or bluntly toothed behind, longitudinally grooved on each side,, 
the margins and centre raised; posterior coxe widely separate ; intercoxal process very broad, the apex 
feebly rounded and almost truncate. Apterous. 
This genus will include three species from Mexico. The shape of the mentum, 
head, and the elytral epipleure forbid association with the North-American genus Poly- 
pleurus, though the species here described have much the general facies of P. nitidus, 
Lec., an insect found in Florida. P. nitcdus itself differs greatly from the type of the 
genus (P. geminatus, Sol.) in the structure of the antenne, tibie, and tarsi, and can 
scarcely be considered congeneric with it. 
Mitys is also allied to Chileone, Hypaulaxr, and Hipalmus, F, Bates; and may be 
known from those genera by the characters given above. 
1. Mitys inflatus. (Tab. V. fig. 7; 7a, mentum and labial palpi; 7 d, maxilla 
and maxillary palpus.) 
Ovate, convex, black, slightly shining. Head finely and rather closely punctured ; prothorax about as long as 
BIOL. CENTR.-AMER., Coleopt., Vol. IV. Pt. 1, July 1885. 00 
