260 PASSALID^. 



of three long terminal lamellae and three shorter supplementary^ 

 ones. Head asymmetrical, the supraorbital ridges sharply- 

 elevated, united behind by a continuous curved ridge and 

 sometimes produced into outer marginal processes in front ; 

 the imier marginal processes very unequal, the left one long 

 and oblique. Parietal ridge strong and sharp. Pronotum 

 with incomplete median groove or none. Maxilla with the 

 inner and outer lobes simple, long and slender. Mentum 

 broad ; ligula stout, not acuminate, the labial palpi dilated, 

 the last joint small. 



I have united 0])hrygonius and Aceraius, which differ only 

 in the degree of hairiness of the sides of the elytra. No sharp 

 dividing line can be drawn in this respect. 



Key to the Species. 



1 (4) Sides of the elytra thickly clothed 



with hair. * 



2 (3) Head bearing four marginal pro- 



cesses grandis Burm., p. 260. 



3 (2) Head without outer marginal pro- 



cesses helferi Kuw., p. 261. 



4 (1) Sides of the elytra without thick 



hair. 



5 (6) Lamellaeof the antennal club short ca?i<ori Perch., p. 262. 



6 (5) Lamellae of the antennal club long birmanicus Grvl., p. 263. 



158. Aceraius grandis. (Plate XXIII, fig. 17.) 



Passalus grandis Burm., Handb. Ent. v, 1847, p. 463. 

 Aceraius grandis Gravely, Mem. Ind. Mus. iii, 1914, p. 231 ; op. 

 ciLxn, 1918, p. 92. 



Very large and stout, with the sides of the elj'tra and meta- 

 stemum and the upper surface of the middle tibia thickly 

 clothed with hair. The head is closely punctured, the punc- 

 tures bearing short erect setae. The supraorbital ridges are 

 sharj^ and long, being produced as blunt outer marginal 

 processes, the left one long, tapering and directed straight 

 forward or inclined slightly inward, the right one shorter and 

 more or less triangular ; the inner marginal processes strong, 

 the left one long, inclined inwards, rather parallel-sided and 

 obliquely tnnicate at the end, the right one short and broad. 

 The median tubercle is sharji but not strong, and the frontal 

 ridges are widely divergent. The pronotum is very smooth, 

 without median groove, but with fairly strong punctures near 

 the lateral margins and the sides of the front margin. The 

 elytra are deeply striate, the striae unpuncturt^, the three 

 outermost intervals are densely punctured and thickly hairy 

 in their anterior })art, and the seventh and ninth intervals are 

 punctured throughout, the former less closely. The sides of 



