neio Species o/llistericla?. 233 



them are others very fine; the 

 pygidium is similarly punctured, but the larger points do not 

 extend to the apex ; the prosternum, keel bistriate, strise 

 nearly parallel to each other, but slightly widening out behind, 

 and they are not joined in front, there are a few fine punctures 

 between the strise, and the surface is microscopically strigose, 

 the punctuation is denser on the anterior lobe ; the meso- 

 sternum is marginate and the acumination rather minute, the 

 surface with that of the metasternum has a very fine punctua- 

 tion ; the anterior tibise are 5-dentate. 



In general outline this species agrees with P. morulusy 

 Lew., which is the only other elliptical species known. 



Hah. St. Thomas's Island, Gulf of Guinea. 



Stenotrophis, gen. nov. 



Body short, cylindrical, and truncate; head retractile, 

 epistoma excavated, mandibles very robust and very strongly 

 dentate ; antennae, club orbicular in outline, joints 3-7 

 moniliform and equal in size ; antennal fovea is in the ano-}e of 

 the thorax and not open as in Pachycrcenis ; tliorax transverse 

 and marginate at the sides ; elytra, dorsal strife short and in- 

 complete ; prosternum, keel very narrow, parallel at the sides 

 and bistriate ; mesosternum produced in the middle; pyo-idiuin 

 semicircular and convex; anterior tibiae with 9 coequal and 

 equidistant teeth, the aPiterior femora are grooved and strono-lv 

 dilated at the tibial end on the anterior edge, somewhat 

 similar but more explanate than in Pkelister Simonii, Lew. 

 (fig. 1, Ann. & Mag. Nat. Hist. p. 46, July 1869). 



Type Pachycrcerus cavi/rons, Lew. 



This genus should be placed next to Chalcurga^^ in which 

 the antennal fossette and narrow sternal keel are very similar. 



I have recently received four examples of 8. cavifrons 

 Lew., from Usambara which are metallic blue, but the type 

 is brassy green and is from N. Kamerun. I cannot see any 

 other difiTerence, and so conclude that the species has a wide 

 range. Mr. Guy A. K. Marshall has lately found Macro- 

 sternus Lafertei, Mars, (originally recorded from Sene<Tal) 

 in Gazaland, and I believe there are other species wliich 

 extend from coast to coast on the African continent. 



ExoSTERNUS, gen. nov. 



Body oval, robust, rather convex, somewhat metallic • 

 head retractile, forehead flat and punctate, epistoma distinctly 

 separate; thorax marginate and the antennal fossettes are in 

 the angle and not open like those of Pachycrarus ; elytra 



