igi4.] F- H. Gravely : An Account vf the Oriental Passalidae. 195 



turn and have the supra-orbital ridges continuous with the supra-occipital ridge. The 

 Tiberius here referred to is T. ktiwerti, Arrow {=cancrus, auct.) and I have had to 

 create a new genus Tiberioides for the reception of this species, of Chilomaziis borealis, 

 Arrow, and of a new species {T. austeni) in the Indian Museum collection which com- 

 bines some of the characters distinguishing the first two from one another. 



Kuwert's reason for including "Tiberius cancrus" and the genus Episphenus in 

 the Macrolininae instead of among his "second ga ' ' groups, was that they were neither 

 asymmetrical nor possessed of a mentum marked by grooves cutting off a small area 

 ("furchenbegrenztes Schild") from the rest. Either of these characters occurring 

 without the other would have been sufficient to place them among the ' ' second ga ' ' 

 groups, and they appear to me to be of much less importance than the two characters 

 referred to above, in each of which they differ from the rest of the group in which 

 Kuwert placed them. Moreover, the genus Episphenus closely resembles the genera 

 Chilomazus {=Laches) and Basilianus in the texture of the upper surface of the head, 

 and forms with them a series ranging from complete symmetry to a high degree of 

 asymmetry, but otherwise remarkably alike. [See also below, p. 316]. 



Turning now to Kuwert's " second qa" groups, it is clear that of the grooves and 

 depressions found in the mentum of different genera of his Ivachinae, only the lateral 

 depressions, found nowhere except in the Far Eastern genera Mastochilus^ and 

 Analaches,^ are primary scars. Consequently these two genera may be separated from 

 the Oriental Chilomazus and partly Oriental Epilaches.^ On the same grounds the 

 Oriental genus Heterochilus , which is without primary scars, can be separated from 

 the remaining genera — none of thefn found in the Oriental Region — of the group in 

 which Kuwert placed it, and placed near the Oriental genus Aceraius, a procedure 

 which Zang has already advocated (1905a, p. 167) on different grounds. 



The new classification resulting from this rearrangement of genera , and necessi- 

 tated by the definitions of the subfamilies Aceraiinae, Macrolininae and Gnaphalocne- 

 minae given above, appears to me to be more natural than the old ; and all the 

 changes advocated have the effect of bringing classification more nearly into line 

 with distribution. 



The subfamily Aceraiinae is almost entirely confined to the Oriental Region, and 

 its distribution, as will be seen later (pp. 311-313), follows such definite lines that the 

 one striking case of discontinuous distribution which it appears to show — that of the 

 genus Epilaches — wiU probably prove to be a mistake. E. filius, Kuwert, from the 



' Kuwert omits the scars in his figure of the type of meiitutn found in this genus. They are men- 

 tioned, however, in Percheron's description of Passahis sexde.ntatus { = Mastochilus polyphyllus according 

 to Kuwert) ; they are well developed in the specimens in the Hamburg Museum determined by Zang 

 M. polyphyllus ; and Kuwert himself mentions in his descriptions of both species of the genus the presence 

 of scars, which he describes in terms that seem unlikely to refer to the small grooves he figures close to 

 the middle of the anterior margin. Concerning the correct form of the name of the genus (whether 

 Mastochilus or MastacJiilus, see Zang, 19036, p. 418. 



* Concerning Kuwert's confusion of the names Analaches and Epilaches, see below p. 283. 



