324 Mr. G.R. Waterhouse on some Heteromerous Coleoptera. 
Elytra elongated, but little broader in the middle than at the base, 
rounded at the extremity; distinctly broader at the base than 
the thorax at the same part, and with a transverse ridge; the 
humeral angles prominent ; lateral keel distinct. 
Legs moderate ; the tibize simple ; tarsi rather shorter than the 
tibiee. 
Grammicus chilensis. Gramm. rufo-piceus; corpore elongato, sub- 
depresso ; capite thoraceque rugoso-punctatis; thorace bicostato ; 
elytris singulis quadricostatis, seriatim punctatis, subtransversim 
ruyosis.—Long. corp. 13 lin. 
This little insect was found by Mr. Darwin at Valparaiso. It 
is exceedingly lke a Tagenza, having the small, narrow, elongated 
form, and in having the thorax and elytra furnished with distinct 
longitudinal ridges it will bear a still closer comparison with 
M. Solier’s genus Microtelus ; from both these genera, and indeed 
all the Tageniide, it differs in having the eye situated entirely above 
the lateral groove of the head*; from Tagenia it may moreover 
be distinguished by the antennz being of equal width throughout, 
the joints being less transverse, and mdeed presenting a nearly 
square outline, though rather broader than long,—by the penul- 
timate jot beimg distinctly longer than the rest, and longer 
than broad, and the terminal jomt smaller and confounded with 
the penultimate, to which differences may be added that of the 
mentum not being notched at the side. The long head and equal 
joints of the antennz (if we except the last two) at once distin- 
guish the present insect from Microtelus ; the epistoma or clypeus 
moreover is not emargimated in front, and in the genus last men- 
tioned we do not find the penultimate joint of the antenne longer 
than the rest. 
The two longitudinal keels on the thorax divide its dorsal sur- 
face into three equal parts, and the imterspaces are flat : the keels 
or ridges of the elytra are nearly equidistant, sharp and distinct ; 
and in the interspaces are two rows of distinct punctures, each 
row being placed close to a ridge; and there are moreover some 
irregularly transverse ruge, but these are by no means strongly 
marked. 
* In Leptinoderes I find the nearest approach, in the extremely con- 
tracted condition of the eye, to the present insect. 
