46 RHYNCHOPHORA. 
Hab. Mexico, Toxpam (Sallé), Bobo (Hége); Nicaragua, Chontales (Janson); 
Panama, Tolé (Champion). 
Head elongate ; rostrum not abruptly dilated at the apex, the sinuous carine of the 
prorostrum strongly elevated. ‘Thorax concolorous with the rest of the surface, with- 
out any darker marks. ‘The elytra are rather long and narrow, quite dull, with the 
serial punctuation indistinct, the interstices a little convex, but broad and not at all 
carinate, the apices distinctly bidentate; the yellow marks placed as follows: third 
interstice with a basal line, that may extend one-third or only one-sixth of the length, 
behind the middle with a dot forming part of a transverse fascia, and at the apex with 
a longer line; fourth, fifth, and seventh interstices, and sometimes the sixth also, each 
with a short mark behind the middle forming, together with the similar mark on the 
third interstice, a transverse fascia, the more external mark being placed a little farther 
back than the others; fourth interstice with a short mark on the middle, the fifth 
and sixth each with a very short one placed more forwards than the last-mentioned 
one; eighth interstice with a short line behind the shoulder; humeral angle with a 
yellow dot. ‘Terminal ventral segment of male set with short yellow sete. 
This species is apparently rare ; though so widely distributed in our region we have 
received only ten examples. The two specimens from the State of Panama have the 
basal yellow line on the third interstice longer than it is in the specimens from the 
other localities. The insect is comparatively longer and narrower than our other species 
of the genus. The anterior parts of the body are sometimes vaguely infuscate. ‘Two 
males from Chontales exhibit the peculiarity of having the palpi and lobes (I presume 
of the maxille) very elongate, as shown in our figure; while specimens from Mexico 
and Panama do not exhibit this exceptional structure. A similar exsertion of the 
mouth-parts occurs in some examples of 4. flavolineatus. 
Arrhenodes dispar and several other species of the genus have the elytra marked 
almost as in A. concolor, but in A. dispar the head is short. I have seen specimens 
of an Arrhenodes from the Amazons that come very close to A. concolor, but they have 
the yellow mark on the eighth interstice reduced to a mere dot. 
5. Arrhenodes angulicollis. 
Arrhenodes angulicollis, Gyll. in Schénh. Gen. Cure. i. p. 818°; v. p. 472°. 
Hab. Mexico ?.—Braziu !. 
It is very doubtful whether this insect was really found in our region. It was 
described in the first place! from Brazil on male examples; Mexico being added in a 
subsequent volume as a locality of the female®. The elytra are black, but in markings 
they agree, according to description, with A. concolor, except that the apical spines are 
ferruginous. Boheman! describes the head as short ; if this be correct, it would 
bring A. angulicollis very near to the common South-American d. dispar. 
