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species, but oaly because I have before me some examples from 

 the neighbourhood (Port Essington) that Hope cites as its 

 habitat. The description is quite insufficient, and the name 

 absurd, — as the author himself in his diagnosis says " elytris 

 nigris." The phrase " thorace trigono " is very puzzling ; I do 

 not know of any OnthojDliagus that it would suit; following 

 words describing the structure of the summit of the retuse front 

 forbid the supposition that the phrase refers to that part having 

 three angular projections. I have concluded that the reference 

 must be to the strong dilatation of the prothorax near the front, 

 making the front itself appear (when looked at casually, from 

 behind, obliquely) very much wider than the base, so that with a 

 little imagination the segment seems to have a certain resem- 

 blance to a triangle with the apex truncate. One of the speci- 

 mens before me happened to be mounted in such a manner that 

 this similarity is certainly traceable. The only other explanation 

 I can suggest is that "thorace" may stand in error for " clypeo." 

 " Capite ante oculos furcato "' I take to refer to the hornlike 

 upward prolongment of the ends of the frontal lamina. The 

 species before me varies in colour from reddish piceous to black 

 and is nitid (the club of the antennae testaceous) ; the base of its 

 pronotum is not strictly speaking margined, but a narrow mar- 

 ginal space is flattened, and not continuing evenly the hind 

 declivity of the surface may be called a narrow pseudo-margin. 

 The clypeal suture forms a carina abbreviated at each end ; the 

 frontal lamina is well-marked and its ends are elevated very 

 variably; the clypeus is acuminate in front, with sinuous side s 

 and reflexed apex ; the eyes resemble those of 0. capella, Kirby 

 (fairly wide, and distinctly facetted) ; the pronotum is rather 

 closely and not finely (but not deeply) punctulate (the punctures 

 very sparse and faint on the retuse front and also near the base); 

 the middle of the retuse front is topped by a strong widely and 

 sinuously arched transverse carina ; the sides of the pronotum 

 are extremely strongly sinuate behind the middle but (viewed 

 from above) non-sinuate in front of the middle ; the front angles 

 are roundly (but not widely) obtuse, the hind angle? well defined 

 and widely obtuse ; the elytra are somewhat strongly crenulate- 

 striate, the crenulations inclining towards being punctures ; the 

 elytral interstices are more or less convex (especially towards the 

 sides) aud evenly sparsely and not very finely punctulate ; the 

 pygidium is coriaceous and somewhat coarsely punctulate ; the 

 metasternum is finely sparsely and not deeply punctulate. Tf 

 (as I believe to bo the case) I have both sexes before me, the 

 sexual differences are very feeble, the female having the clypeus 

 less acuminate in front, the ends of the frontal lamina less pro- 

 duced and the retuse front of the pronotum less elevated and 

 more distinctly punctulate. 



