StapliijlinidcB of the Amazon Valley. 201 



lengtli, loth considerably broader than the 4th; 11th 

 joint yellowish at the extremity, obtusely pointed. Palpi 

 yellowish ; mandibles rather long and slender at the ex- 

 tremity. Head as broad as the thorax, much narrowed 

 in front, the hind angles rounded, Avitli an elongate oblique 

 puncture on each side between the eyes, a similar one 

 behind tlie eye, and one or two other jjunctures near the 

 back ; otherwise inipunctate, very shining, and of a beau- 

 tiful violet-blue colour. Thorax a little narrower than 

 the elytra, longer than broad, straight at the sides, similar 

 in colour to the head, very shining, Avith three or four 

 coarse pimctures on each side close to the front ; otherwise 

 impunctate. Scutellum with three or four punctures. 

 Elytra shining dark blue, quite as long as the thorax, 

 sparingly biit rather coarsely punctured. Hind body 

 shining black, the hind margin of the 6th and the whole 

 of the 7th segment bright yelloAv, very sparingly pimc- 

 tured. Legs and prosternum pitchy. 

 Ega ; one specimen. 



6. XantlioUnus temporalis, n. sp. Niger, nitidus, 

 capite thoraceque violaceis, elytris nigro-cyaneis, ano 

 flavo ; thorace ad angulos anteriores parce punctato. 

 Long. Corp. 7^ lin. 



This insect is peculiar by the very thick hind part of 

 the head and by a peculiar foi-m of the mandibles. An- 

 tennffi rather longer than the head, nearly black; 3rd joint 

 nearly twice as long as the 2nd; joints 4 — 10 transverse, 

 scarcely differing in length, but the lOth broader than the 

 4tli ; 1 1th joint obtusely pointed, yellow at the extremity. 

 Palpi slender and elongate, yellowish. Mandibles pitchy 

 black, elongate, the left one longer than the right and 

 much curved towards the extremity, and near the ex- 

 tremity sinuate or emarginate on the upper edge. Head 

 large, broader than the thorax, narrowed in front, the hind 

 angles rounded, the upper surface rather uneven, a punc- 

 ture on each side between the eyes, a few others on each 

 side near the hind angle and back margin, and behind the 

 eye with a curved broad impression ; it is of a shining 

 violet-blue colour, on the under surface but little shining, 

 and there with shallow longitudinally subrugose sculptxu-e. 

 Thorax scarcely narrower than the elytra, rather longer 

 than broad, slightly narrowed behind, similar in colour to 

 the head, impunctate with the exception of five or six 



