517 



REVISION OF THE GENERA COLPOCHILA 



(INCLUDING HAPLONYCHA), SERICESTHIS AND 



THEIR ALLIES, WITH DESCRIPTIONS 



OF NEW SPECIES. 



By the Rev. T. Blackburn, B.A., Corr. Mem. 



Part I. 



Since the completion of my Revision of the genus Heteronyx I 

 have been studying some of the other Australian genera which 

 belong to the group of Melolonthidce called by M. Lacordaire 

 " Ifeteronycides." This group .seems to fall naturally into three 

 subgroups, — 1st containing genera with the elytra abbreviated 

 ( Liparetrus and its allies), 2nd those with the elytra normal and 

 the claws simple ( Sericesthis, &c.), 3rd those with the elytra 

 normal and the claws not simple {Heteronyx and its allies). The 

 2nd of these subgroups consists of the following already described 

 genera, — Sericesthis, Teiura, HaploiJsis, Haplonycha, Colpochila, 

 Colohostoma,* Pachygastra, and perhaps Bijjhyllocera and Homolo- 

 tropus. The last named two genera I have not seen, nor ai-e 

 they sufficiently described, — no mention being made e.g. of their 

 claw structure beyond that the former is said to have simple hioid 

 claws (if this implies that the anterior claws are not simple the 

 statement disassociates it from the Sericesthis subgroup). This 

 second subgroup of Ileteronycides appears to me divisible again 

 into 2 sections, the former having the hind tibiae scarcely dilated at 

 the apex (the width at the apex scarcely greater than in the middle) 



* I think there is very little doubt that Sir VV. Macleay's genus Platy- 

 desmiis is identical with this ; Burmeister's suggestion that Colobostoma 

 may be identical with Microthopus, Hope (near Liparetrus), is almost 

 certainly mistaken. Blanchard's description (Cat. Coll. Ent. 1850) seems 

 to have been taken from the original type of Sericesthis rtifipentiis, Boisd. , 

 and thei-e seems to be scarcely a doubt that the insect Blanchard described 

 was identical with Platydesmus, Macl. Microthopus is a very dififerent 

 insect from Western Australia. 



