Lea — Australian Dung Beetles 363 



ONTHOPHAGUS. 



Specimens of the Australian species of Onthophagus known to Blackbnrn 

 are before me, with the exception of O. hipustnlattis, 0. carmodensis, and 0. 



m 



helmsi. T have carefnlly tried to follow his grouping of the species, Init am 

 unable to do so, even his Group 1, consisting of a few large species, appears to be 

 scarcely distinguishable, b}' the basal edging of the pronotum alone, from some 

 members of other groups, as many of these have the marginal edging even 

 throughout, although not so highly elevated as on those he referred to Group 1. 

 The species of ({roup 4 might well be distributed between those of all groups, 

 ■except 1. The difference between a flat or feebly convex base and one very 

 faintly concave is so slight that it can seldom be of much use, so that I follow 

 Arrow, who considered that "The supposed difference in the prothoracic margin 

 is illusory. ' ' Blackburn considered that tables based largely on male characters 

 are not desirable, but they have at least the advantage of enabling many species 

 to be quickly identified, thus serving at least one of the main uses of a table. 

 Probably had he used the facets of the eyes, for the primary divisions, the tables 

 would have been more satisfactory, even although they apparently alter on some 

 specimens on drying, their true nature is generally at once evident if they are 

 viewed from oblique directions ; the clypeal suture could also have been used to a 

 greater extent, although with some species it varies sexually. 



ONTHOPHAGUS AUSTRALIS Guer. 



Plate viii, figs. 31-33. 



The whole upper-surface of fresh specimens of this species has a curious 

 ■satiny gloss; the interocular horns and ridge of the male vary considerably. 



ONTHOPHAGUS MASTERSI Macl. 



Plate viii, figs. 34, 35. 



In Blackburn's table this species is separated from 0. australis by being 

 ^' Black, not at all- metallic " ; but on the male the prothorax has sometimes an 

 obscure metallic-green gloss; structurally it is extremely close to some forms of 

 0. australis. 



ONTHOPHAGUS MACROCEPHALUS Kirby. 



Plate viii, figs. 36, 37. 



The cephalic horn on the male of this species sometimes extends almost to the 

 ■elytra, but it is usuallv much shorter. 



