species of Heteromerous Coleoptera. 323 
its body is rather less narrow in proportion, and the elytra are 
more convex; they are considerably broader than the thorax. 
The thorax is rather broader than long, broadest in front, and 
considerably contracted behind. The elytra have the punctures 
forming the ordinary striz rather small, and there are some very 
minute punctures between these rows, and these have a tendency 
to a linear arrangement, there being two irregular rows of them 
on the fore part of the elytra, and one row on the hinder part. 
Mr. Darwin found this insect at Port Desire in Patagonia. 
Family TAGENIID/A. 
GRAMMICUS, noy. gen. 
Head with obtuse posterior angles, which are rather remote from 
the thorax (the head bemg furnished with a long neck, which 
however is but little seen), longer than broad, the sides straight 
and parallel and with a lateral keel; the part in front of the 
eye as long as the hind part ; the clypeus contracted and trun- 
cated in front ; the fold coverimg the base of the antenne but 
little prominent, not produced laterally beyond the outline of 
the head, its margin somewhat reflected: cheek-plate consi- 
derably produced in front ; the space between it and the men- 
tum, for the maxilla, narrow. 
Hye small, nearly round ; situated entirely above the lateral groove 
of the head, its vertex directed upwards. 
Antenne about equal in length to the head and thorax taken 
together ; very thick, the jomts equal to each other, with the 
exception of the last two, and presenting a square outline ; 
each joint is jomed to the next by a narrow neck ; the penul- 
timate jomt longer than the rest ; the last very small, some- 
what pointed, and so joimed to the last that the line of separa- 
tion is with difficulty perceived. 
Mandibles short and stout, very broad and bidentate at the ex- 
tremity. 
Mazaillary palpi vather long and with the joints moderately stout ; 
the first and second obconic; the third rather the longest, of 
an elongate-ovate form, the broadest part however rather be- 
yond the middle. 
Mentum moderate ; transverse, hexagonal, slightly emarginated 
in front, not covering the maxille. 
Thorax fully as long as broad, slightly trisinuated in front; the 
hinder margin straight (or very nearly so), the lateral margins 
parallel on the fore half of the thorax, and from the middle 
gradually contracted to the hinder angles; the angles right 
angles ; the sides keeled. . 
Scutellum very small. 
2A2 
