BY THE REV. T. BLACKBURN. 415 



Clialcopterus would be a syuonyni of Amarygmus^ and a new 

 name vvould be required for the Amarygmi (so-called) with bifid 

 mandibles. Nevertheless, until further evidence is forthcoming, 

 if M. Blessig's separation from Amarygnins of those species 

 winch differ in the form of their mandibles from A. speciosus is to 

 be accepted (and I think it ought to be), M. Blessig's claim of 

 Dalman's name for the species with bitid mandibles seems 

 decisive, and therefore those species of the old genus Amarygmus 

 which have mandibles widely and evenly truncate at the apex 

 ought to be relegated to Ghalcopterus. 



.For me, therefore, the Australian Amarygmides hitherto named 

 all belong to two genera, distinguished thus : — 



A. Apex of mandibles bifid Amarygmus. 



AA. Apex of mandibles widely and evenly truncate Ghalcopterus. 



I am surprised that all the authors subsequent to M. Blessig 

 have disregarded the form of the mandibles (Sir W. Macleay, 

 however, implies, P.L.S.N.S.W. 1887, p. 550, that he had not seen 

 M. Blessig's memoir), especially as Mr. Pascoe (Ann. Nat. Hist. 

 1869) actually mentions Blessig's remarks on it ; for even if it 

 were to be inferred that they regarded the character as too trivial 

 to be treated as generic, it certainly cannot be questioned that it 

 is most valuable for subdividing an aggregate of insects in 

 which sharply defined difFei'ences are none too plentiful, and there 

 are few specimens in which the mandibles are so hidden that 

 there is the least difficulty in discerning their form. In the 

 Chalcopteri the exposed surface of the mandibles (supposing them 

 to be in contact with each other in repose) is evenly convex in 

 the apical portion, the apex itself being quite straightly truncate, 

 while in Amarygmus the surface is traveised from base to apex 

 by a deep sharply defined sulcus, the impression of which at the 

 apex interrupts the continuousness of its truncation. 



Turning to the species named up to the present time, we are 

 encountered by the principal difficulty in dealing with the revision 

 of the Amarygmides. The number of names that have been used 

 is 67. Of these I am able to say confidently that 11 have 



