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 striae 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^. 



Grammicus, nov. gen. 



Head with obtuse posterior angles, which are rather remote from 

 the thorax (the head being 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 covering the base of the antennae 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. 



Eye small, nearly round ; situated entirely above the lateral groove 

 of the head, its vertex directed upwards. 



Antenna about equal in length to the head and thorax taken 

 together ; very thick, the joints equal to each other, with the 

 exception of the last two, and presenting a square outline ; 

 each joint is joined to the next by a narrow neck ; the penul- 

 timate joint longer than the rest ; the last very small, some- 

 what pointed, and so joined 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. 



Maxillary palpi rather long and with the joints moderately stout ; 

 the first and second obconic ; the thii4 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 maxillae. 



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 



