1914-] F- H. GravEIvY : An Account of the Oriental Passalidae. 247 



Genus TRAPEZOCHILUS, Zang. 



Trapezochilus nobilis (Kuwert)'. 



PI. xiii, fig. 48; text-fig. 5, C-D. 



Regd. No. ^ -f Tavoy Museum Collector. 



I have also seen a series of specimens from Taiping, 4000-5000 ft., in the collec- 

 tion of the Königliches Zoologisches Museum in Berlin ; and two specimens from 

 Perak in the British Museum. 



Description. — Length 35-41 mm. Lahrum hairy and punctured ; anterior margin 

 straight or slightly concave, with a more or less indistinct denticle in the middle; 

 angles rounded, symmetrical or very nearly so. Antennae with a more or less 

 indistinct lamelliform process on the fifth joint, lamellae of subsequent joints of 

 gradually increasing size, all short and stout. Upper tooth of mandibles usually 

 rectangular sometimes blunter, minute; terminal teeth large, the two upper ones 

 broadest in the vertical plane, the lowest one horizontal ; anterior lower tooth distinct 

 and sharply pointed on the left side, obsolete or minute and fused with base of 



Text-figure 5. 



A. Paro.pelopides symmetricus, anterior margin of head x 4. 



B. ,, ,, right mandible x 4. 



C. Trapezochilus nobilis, anterior margin of head x 4. 

 D ,, ,, right mandible x 4. 



E. Trapezochilus resbectabilis, anterior margin of head x 4. 



lowest terminal tooth, on the right. Mentum punctured laterally, smooth between 

 and behind the oblique groove-like scars. Head strongly rugose in front, smoother 

 behind, the surface polished throughout. Outer tubercles somewhat variable, 

 approximately symmetrical, each composed of three conical denticles of which the 

 innermost is usually the largest ; the outermost is usually slenderer or quite short 

 and blunt; the middle one is small and set a little further back, its position is 

 variable, and may be different on opposite sides of the same specimen, it is some- 

 times obsolete on the right or on both sides. Anterior angles of head containing a 

 little more than 120° ; canthus rounded externally. Parietal ridges curved slightly 

 forwards. Supra-orbital ridges smoothly convex behind, excavate in front, their 

 upper margin curved (not angular) in front when seen in profile. Pronotum 

 smooth and polished, not obviously punctured except in the scars and margi- 

 nal grooves ; marginal grooves widely discontinuous in front, almost continuous 

 behind; median groove rudimentary or absent. Lateral plates of lower surface 



' This species has proved not to be distinct from the next ; and the names applied to them here 

 must both be discarded in favour of dorsalis, Kaup (see below, pp. 297-8) 



