CLASSIFICATION OF THE RHYNCHOPHOROUS COLEOPTERA. 457 
sometimes finely carinate, not expanded at tip; the antennal 
grooves are very narrow, parallel at their origin, and usually sud- 
denly deflexed, though sometimes (Phyllobius) very short and 
straight. The eyes vary in form and the prothorax is lobed or 
not. The prothorax is usually bisinuate at base, with the hind 
angles acute, though sometimes truncate. The elytra are usually 
free, with prominent humeri, and the wings well developed: 
though sometimes they are connate, with rounded shoulders. The 
accessory mandibular piece is long and falcate in both, and the 
support at the tip of the mandible is circular and not prominent ; 
characters of great moment when associated with the peculiar form 
of body. 
Two tribes are indicated by a difference in the outer stria of the 
elytra: 
Outer stria of elytra entire. ... +. + «+ PHYLLOBINI. 
Outer stria of elytra abbreviated or interrupted TANYMECINI. 
The first tribe is represented by Pachnæus, and Phyllobius in 
the Atlantic States, and by Scythropus on both slopes of the con- 
tinent. Of these Pachnæus has the eyes transverse, and the pro- 
thorax lobed at the sides in front, while in the others the eyes are 
rounded, and prominent, and the front outline of the prothorax 
is straight. The species are all winged, and the humeral angles 
are obtuse and well defined. The base of the prothorax is trun- 
cate in all the genera except Pachnzus, where it is distinctly bi- 
Sinuate. 
Macrostylus, a Brazilian genus recently found in Texas, is an 
anomalous member of this tribe. The antenna are very long and : 
slender, and the joints of the club seem to be quite separate and 
free. It is of very small size, and has the elytra connate and the 
humeral angles not prominent; the beak is not channelled, but 
otherwise resembles the beak of other members of the, tribe. The 
claws are connate almost to the tip, as in Phyllobius, etc., while 
they are separate in Pachneus. There are thus three groups in- 
dicated x 
Prothorax lobed in front; claws separate: . . - Pachnei. 
Prothorax not lobed; claws connate: 
Humeri prominent, elytra free: - + + + + + Phyllobii. 
Humeri not prominent, elytra connate: . - . Macrostyles. 
The Tanymecini resemble in form the Phyllobiini, but are readily 
distinguished by the outermost stria of the elytra being confluent 
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