342 Mr. A. Murray on Coleoptera from Old Calabar. 



palpisque piceis ; mandibulis piceis, planis, mai-gine exteriore 

 reflexo ; thorace marginibus (prsecipue antice) depressis, linea 

 sublaterali arcuata; elytris pnnctato-striatis, interstitiis con- 

 vexis ; tarsis piceis^ anticis pallidioribus. 

 Long 5i lin.^ lat. 3| lin. 



Broad and convex ; black, smooth, and impunctate, with a 

 dull, somewhat silky lustre, occasioned by a very fine aciculated 

 punctation, scarcely visible except under the compound micro- 

 scope. Head smooth, with a slight depression along the front, and 

 with two small pits between the eyes ; middle tooth of the men- 

 turn with a tendency to become bifid ; antennae piceous, first three 

 joints shining, the rest pubescent and more dusky ; palpi piceous; 

 mandibles piceous, flat, rather thin, circular exteriorly, straight 

 interiorly, except at the point, which has a rounded tooth; 

 exterior margin slightly raised and reflexed posteriorly ; clypeus 

 slightly emarginate, with a deep square depression in the middle 

 of the anterior margin, and two large fovese in each of the 

 anterior angles. Thorax convex, without marginal line, except 

 a very faint one on each side in front, with a linear depression 

 from each anterior angle reaching almost to the basal margin, 

 curved inwards, deepest in front, and leaving a broad marginal 

 space widest behind : the appearance of this line reminds one 

 of a bridle lying on the neck of a horse ; it is, however, very 

 faintly recurved near the base : dorsal line faint, reachmg neither 

 to the anterior nor basal margins. Scutellum large. Elytra 

 punctatc-striate ; interstices convex ; the short scutellar stria 

 along with the sutural stria converging to meet the third and 

 fourth strise at the base; the second stria straight; the strise 

 deepest towards the apex, which is slightly sinuate. Under side 

 with the episterna and sides of the mctasternum punctate; sides of 

 abdomen slightly punctate ; the prosternum slightly prolonged 

 behind, with the prolongation margined. Tibiae short ; anterior 

 tibifc broad and triangular ; anterior tarsi piceous, in the male 

 with the first three joints very broad and transverse, and the 

 fourth very small. 



The most striking character in this species is the form of the 

 mandibles and the projecting prosternum; the former might 

 perhaps justify its establishment as a subgenus, and the latter 

 would seem to approach it to the germs Lonchosternus of Laferte, 

 of which the only character differentiating it from Docks is the 

 prosternum prolonged as in Hydrophilus. The projection here 

 has no pretensions to such an extensive prolongation, but it 

 may be viewed as the passage leading to it. The species is 

 readily recognized by these characters, and by the bridle-shaped 

 de])rcssion on the thorax. 



