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III. On the Australian Species of the Coleopterous Genus Bolboceras, Eirby. 

 By J. O. Westwood, Esq., F.L.S. 



Read March 21st, 1848. 



JDOBBOCEBAS, a genus of Lamellicom beetles, was proposed by the Rev. "W. Kirby, 

 in his excellent memoir published thirty years ago, in the 12th volume of the ' Transac- 

 tions of the Linnean Society,' containing descriptions of New Australian Coleoptera col- 

 lected by Mr. Robert Brown. In his observations appended to the Latin characters given 

 of the genus, as contrasted with those of Geotrupes, Mr. Kirby more especially endeavoured 

 to point out the differences between these two genera, alluding, among other things, to the 

 structure of the outer lobe of the maxillae, but not mentioning (except in the Latin cha- 

 racter) the horny inner lobe, with its bipartite structure, a character (as Mr. MacLeay has 

 shown) of the s highest importance, as distinctly indicating a variety in the operation of 

 manducation, and consequently in the nature of the food of the insects. It is evident that 

 Mr. Kirby's description of the maxilla of Bolboceras was drawn from the inaccurate figure 

 of that part given in pi. 23. fig. 5d, which omits the upper portion of the lower lobe of the 

 maxilla, which is thereby reduced to a single horny point. The maxilla of Bolboceras is, 

 however, almost exactly similar to that of Athyreus ; indicating, in conjunction with the 

 general appearance of the insects, an analogous mode of life, although the difference in the 

 place of insertion of the middle feet must evidently be regarded as a proof of some distinc- 

 tion in the habits of the two genera. 



Mr. Kirby's observations, it will be further seen, are directed to the structure of the 

 antennae and trophi alone. There are consequently two important characters derived from 

 the external structure of the other parts of the insects which separate the two genera, 

 rendering Bolboceras also as far removed from the type of the family Geotrupidce as Athy- 

 reus. These are, the entire structure of the eyes in Bolboceras, whilst each eye is divided 

 into two parts by a distinct septum in Geotrupes, and the want of a patch of orange 

 plush-like hairs on the thighs of the fore-legs, which exists in Geotrupes. 



Mr. Kirby mentions as belonging to Bolboceras, " Sc. mobilicornis, Linn, (of which Sc. 

 testaceus, Fabr., is only a variety), quadridens, Linn., farctus, Fabr., Lazarus, Fabr., Cy- 

 clops, Oliv., &c," together with the new species which he described under the name of 

 Bolboceras australasice, a name now proved to be inapplicable, not only because we pos- 

 sess many Australian species of the genus, but also because the insect so described is but 

 the female of another species. Of the above-mentioned species, the first, Sc. mobilicornis, 

 does not belong to the genus Bolboceras, from which it is distinguished by its bipartite 

 eyes, although the structure of the maxillae and the want of a patch of plush on the fore 

 femora show its near approach to it. It will therefore be proper to apply the generic 

 name of Odontceus, given to this genus by Koppe, instead of Bolboceras, as it stands at 



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