1914-] ^- H. GravbIvY : An Account of the Oriental Passalidae. 229 



the sunken area sometimes indistinct or absent. Head above with frontal area more 

 or less semi-circular, more rarely triangular; ridge joining inner tubercles usually 

 slightly convex in middle, sometimes very strongly so ; left outer tubercle obliquely 

 truncate, truncation straight or very slightly concave, both angles somewhat produced 

 as a rule in fresh specimens; right outer tubercle not much shorter than left, but 

 more nearly triangular, apex single in profile and very acute. Prothorax and meso- 

 thorax as in >4 . horneanus except that the pronotum is less punctured at the sides while 

 its median groove is obsolete, and that the mesosternum is polished, throughout or 

 nearly so, except in the long narrow scars. Metasternum also as in y4. horneanus 

 except the posterior lateral areas in which a variable number of very coarse and often 

 somewhat elongated punctures are more or less extensively developed from in front 

 along the inner margin. Hind coxae and abdominal sterna as in A. horneanus. Elytra 

 not very hairy, the hair all short; tenth rib finely punctured and hairy close to 

 shoulders, ninth rib with a few punctures scattered very sparsely along its whole 

 length, seventh rib with or without even more sparsely scattered punctures. 



Aceraius perakensis, Kuwert. 



Described from three specimens from Taiping, 4000-4500 ft., and one from Mt. 

 Singaleng ; all in the collections in Berlin. 



Description. — I^ength 38-5-42 mm. Labrum as in preceding species; antennae as 

 in following one ; left upper tooth very variable, left anterior lower tooth not so 

 strongly divided as in preceding, mandihles otherwise similar; mentum without any 

 anterior depression, but punctured very sparsely or not at all in middle, not so 

 closely as in following species. Upper surface of head somewhat as in preceding 

 species, but with left outer tubercle stouter, ridge joining inner tubercles concave, 

 inner side of right outer tubercle straighter and more oblique, apex of same tubercle 

 truncate or faintly bifid in profile, canthus usually a little swollen at base ; an- 

 terior angles obtuse as in preceding species, not prominent. Thorax, abdomen and 

 legs as in preceding species; elytra as in following. 



Aceraius möschleri Kuwert. 

 PI. xii, fig. 33. 



Regd, No. '"^ Sinkep Island Moti Ram. 



I have also seen a specimen in the British Museum collection from the Malay 

 Peninsula, and one from lyingga and another from Java in the Berlin collections. 



Description. — Length 36-42 mm. Differs from the following species only in having 

 the- anterior angles of the head scarcely prominent on either side ^ ; and in having the 

 apex of the right outer tubercle less bent outwards as in yl. perakensis. 



' This difference is noted by Kuwert in his brief diagnosis of 1891, but is omitted from the longer 

 one of i8g8, in which the two species are separated by the shape of the anterior margin of the labrum — 

 a character which is always apt to vary somewhat in different specimens of a single species. 



