31 



that are either bifid or appendiculate and those that are simple 

 (disregarding membranous basal appendages) is strictly generic. 

 2. The number of antennal joints and the number of joints 

 forming the antennal club are not generis (although the difference 

 between the number of joints in the club where it is sexual 

 probably is generic). 3. Characters founded upon the granula- 

 tion of the eyes are strictly generic. 4. The difference between 

 simple and geminate striation of the elytra is nearly always 

 combined with reliable generic differences. 5. Marked differences 

 in the form of the clypeus (at least in many cases) are much more 

 generic than differences in the form of the labrum. 6. Differences 

 in the hind tibiae are generic. 



From these general observations I now pass to some remarks 

 on the generic names that at present stand attributable to the 

 Australian Sericoides. These are, I believe, 34 in number 

 {excluding " Melolontha^^ which seems to have been applied loosely 

 by some of the earlier authors to species of this subtribe). Of 

 these Cotidia and Colohostoma are mere names given (without 

 mention of characters) by Boisduval to species that cannot be 

 identified. It is not unlikely that Colohostoma was founded on 

 the insect since named Platydesimis sulcipennis by Sir W. 

 Macleay, but the evidence is not strong enough to upset the later 

 name. I have already discussed this point in Proc. Linn. Soc, 

 N.S.W., 1890, p. 517 (note). 



IIaplonycha = Col2)ochila. Silopa and Hostilina = Heteronyx. 

 Philochlcenia and Omaloplia = Caulobius. Of the names sunk as 

 synonyms in the above statement I regard it as possible that two 

 {Haplo7iycha and PhilochkeniaJ may have to be restored as repre- 

 senting valid genera when the sexual characters of Colpochila and 

 Caulobius are known in a long range of species, but I do not find 

 any other generic character that seems sufficient to confirm 

 them. 



After the above eliminations there remain 28 genera, to the 

 validity of which I am not able to bring any definite objection, 

 but of them there are four that I have not been able to identify 

 among the large collections of Melolonthini that I have examined. 

 On each of these a few remarks seem called for. 



1. Automolus. This genus was formed by Burmeister for a 

 small Tasmanian species, to which Erichson seems to have attached 

 the MS. name Liparetrus angustulus. Burmeister says that its 

 antennae are nine-jointed. Assuming the correctness of that 

 statement I should say that the genus is a good one and that I 

 have not seen it. If it could be that Burmeister had counted 

 the joints incorrectly and that they are really eight (it is easy to 

 go wrong about the minute antennal joints of a small Lip)aretrus) 

 I should suspect that the species is one of those which Sir W. 



