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angulis anticis sat dentiformibus posticis obtusis, sulco 

 lateral! marginali trans basin continuo in medio manifeste 

 subangulatim retrorsum dilatato, carina marginali laterali 

 trans basin minus perspicue continua ; elytris leviter 

 crenulato-striatis, crenulis quam striae vix latioribus, inter- 

 stitiis subtiliter coriaceis parum coQvexis leviter (latera 

 versus magis profunde) punctulatis : pygidio coriaceo sat 

 crebre minus profunde punctulato ; metasterno coriaceo sat 

 sparsim subgrosse punctulato. 

 Maris clypeo antice sat producto plus minusve emarginato, 

 lateribus antice sinuatis ; tibiis anticis sat elongatis, minus 

 latis, extus sat fortiter 4-dentatis. 

 Feminse clypeo antice vix producto subtruncato, lateribus 

 antice haud sinuatis ; tibiis anticis minus elongatis magis 

 fortiter 4-dentatis. Long., 7 — 8;^ 1.; lat., 4 — 4 J 1. 

 There is very little reliable external difference between the 

 sexes except in the form of the clypeus and the structure of the 

 front tibiae. In a well developed male the ends of the frontal 

 lamina are produced upward as quite strong teeth ; in the female 

 and in some males this upward dilatation is quite slight. Looked 

 at from in front the whole dorsal surface of the head behind the 

 clypeal carina seems to consist of this frontal lamina, — the sur- 

 face sculpture of which varies considerably (from being strongly 

 to only lightly rugulose) and does not depend on sex. The species 

 which I regard as 0. atrox, Har., is very close to 0. Cowley i, 

 differing from it chiefly by the hinder elevation on its head being 

 in the male a mere tran verse cariniform line, by the transverse 

 carina above the retuse front of the pronotum having its ex- 

 tremities so far from each other that each of them is directly 

 behind the middle of one of the eyes, by the same carina running 

 in the form of two sides of a triangle the apex of which is 

 truncate and slightly emarginate, by the retuse front of the 

 pronotum being pilose and punctulate, by the interstices of the 

 elytra being flatter, more opaque, and less distinctly punctulate, 

 and by the distance between the external tubercles of the 

 pronotum being a little less than the width of the head, 

 N. Queensland (sent by the late Mr. Cowley). 

 0. lamiiiatus^ Mad. I think I have correctly identified this 

 insect. The sculpture of the front part of the pronotum is very 

 insufficiently described, and there are several species that fit the 

 description in this respect ; but in characterising the j^uncturation 

 of the pronotum Sir W. Macleay says " the greater portion of the 

 rest of the prothorax is punctured," and I find one species (and 

 one only) of this group to which those words apply satisfactorily 

 since on its pronotum the coarse rugulosity that occupies the 

 area immediately behind the retuse front becomes rapidly 



