28 Mr. G. Rh. Waterhouse oz Coleopterous Insects 
Head small, in width not equal to more than half that of the 
thorax ; inclosed m the thorax as far as the eyes; the outline 
of the part im front of the eyes, mcludimg the mandibles and 
labrum, is conical, but taking the arch formed by the outline 
of the clypeus, it is nearly semicircular ;—slightly indented on 
each side of the clypeus. 
Antenne of moderate length; if extended backwards would 
scarcely reach the base of the thorax; slender, the jomts of a 
long obconic form ; the second joint short, the third long, but 
not equal in length to the two following joints taken together ; 
the last three joimts dilated ; the antepenultimate and penulti- 
mate present a triangular outline ; the last joint is about equal 
in size to these, but of an oval form. 
Eyes tolerably large and moderately convex, kidney-shaped, being 
very slightly encroached upon in front by the lateral ridge of 
the head. 
Thorax transverse, narrower before than behind, rather deeply 
emarginated in front, rounded at the sides and bisinuated be- 
hind, where it is closely applied to the thorax: the upper sur- 
face is convex, and there is an impressed line (not very distinct) 
following the margins, but interrupted m the middle of the 
anterior margin: the angles are acute in front and right 
angles behind,—or nearly right angles. 
Scutellum rather small, but distinct ; rounded behind. 
Elytra soldered together, very convex, broader than the thorax 
and of an ovate form, but sinuated in front, where the curved 
outline corresponds to that of the hinder margin of the thorax ; 
the humeral angles somewhat obtuse. 
Presternum with its hinder margin obtuse, notched, and not pro- 
duced posteriorly beyond the anterior coxe. 
Abdomen but little inclosed at the sides by the elytra. 
Legs slender and moderately long ; the tibie nearly cylindrical, 
and terminated by two small spines : tarsi slender ; the hider 
tarsi equal in length to more than two-thirds of ‘that of the 
tibia. 
In general appearance the species of this genus greatly re- 
semble those of the genus Helops, and more particularly those 
shorter-bodied species of which our common Helops striatus may 
be said to form thetype. In size and general form, the Stomion 
levigatus (hereafter described) greatly resembles the insect Just 
mentioned, but its thorax and elytra are more conyex. The Sfo- 
mion galapagoensis is half as large again as the H. striatus, and 
of a much broader form and more convex above : the third species 
of Stomion known to me is considerably less than the H. striatus, 
and of a shorter and broader form. The structure of the mouth, 
ae 
