3i8 



Memoirs of the Indian Museum. 



[Vol.. Ill, 



( A little hair present on elytra at shoulders only ; dentition 

 j always complete, left anterior lower tooth rarely enlarged. 

 j Elytra hairy at sides also; right lowest terminal and anterior 

 I lower teeth almost always rudimentary; left anterior lower 

 I tooth almost always enlarged 

 I 



Ophrygonius, 



Zang, pp. 224 & 284. 



Ace/aius, Kaup, 



pp. 228 & 286- 



APPENDIX II.- 



-KBYS FOR THE DETERMINATION OF SPECIES 

 OF ORIENTAL PASSALIDAE. 



In most of the following keys Oriental species only are dealt with. Of the 

 seven genera occurring in both the Oriental and Australian Regions five {Comacupes, 

 Macrolinus, Gnaphalocnemis [?], Leptaulax and Trichostigmus) are chiefly Oriental, 

 and I have included all their species, basing my definitions of such as I have not 

 seen^ on the descriptions of previous writers. The genera Aulacocyclus and Gonatas, 

 on the other hand, are found mostly in the Australian Region, and as I am unable 

 to give any revised definitions of their species, only the Oriental forms are included 

 in the keys. 



Genus Comacupes, Kaup. 



( Mesosternum strongly punctured all over, abdominal sterna 



' with at least a few hair-bearing punctures in fresh specimens. . .. .. 2. 



j Mesosternum unpunctured except at sides, abdomen unpunc- 



l tured and hairless .. .. .. . C. foveicollis, -p. 26y. 



Lower margin of overhanging portion of central tubercle of 



head usually rather long, always horizontal, anterior part of 



upper margin descending obliquely to meet it in a more or less 



acute angle ; upper surface of same tubercle usually more or 



less distinctly grooved longitudinally, or excavate . . . . . . 3. 



Lower margin of overhanging portion of central tubercle of 



head short, or ascending obliquely to meet upper margin which 



is always horizontal; tubercle usually truncate or concave 



anteriorly, not sharply pointed, narrower, keeled or rounded 

 ^ above . , . . . . . . . . . . . . 5. 



Central tubercle pedunculate (almost as in Aulacocyclus) 



Central tubercle not pedunculate 



Central tubercle broad and strongly excavate above 



Central tubercle narrow, at most longitudinally grooved above 



Whole anterior end of central tubercle raised well above supra- 

 orbital ridges, not truncate or concave in front . . 



Central tubercle less elevated, truncate or concave in front, 



very variable . . 



C. basalis, p. 267. 



4 

 C. cavicornis, pp. 204 & 268. 

 C. stoliczkae, pp. 206 & 268. 



C. masoni, pp. 207 & 268. 



C. cyclindr accus, pp. 207 & 

 269. 



^ Several species not seen in time for inclusion in the descriptive part of this paper (part 4) are 

 redefined here from personal observation. The only species not so defined are those marked with an 

 asterisk ( * ) in part 6. 



