404 Journal of the Asiatic Society of Bengal. [November, 1912. 
of the revised system of classification that I have found it 
necessary to adopt 
The Passalidae inhabiting the Indo-Australian region all 
fall into one or other of two groups whi i 
this section of the family as containing one sub-family only to 
which the name Aulacocyclinae must be applied. 
The second section of the family as found in the region 
under consideration can conveniently be divided into five sub- 
families. The first contains only the one genus Pleurarius, 
which is distinguished among other characters by combining the 
presence of only three well-developed antennal lamellae with 
the presence of only one pair of processes of the anterior 
margin of the head between the ends of the supra-orbital ridges. 
For this sub-family the name Pleurariinae must obviously be 
used. 
The next sub-family may be called the Aceraiinae and 
includes all the remaining species in which true lateral scars are 
absent from the mentum. With the single exception of Epila- 
ches | infantilis whose grouping with a scarless form will prob- 
ably, I think, prove to be one of Kuwert’s many little errors, 
and of Aceraius prosternisulcatus (? =grandis) which may perhaps 
have been recorded from Molucca in error for Malacca, this 
e’s Line; and it occurs in every part of this 
region inhabited by Passalids of any kind except perhaps the 
Andamans and Nicobars* It shows very nicely the close 
relationship which may be found between symmetrical and 
asymmetrical forms. In Ceylon we have the symmetrical 
genus Episphenus and the commoner and slightly asymmetrical 
| Kuwert has transposed the generic names Hpilaches and Analaches 
in his ‘* passaliden dichotomisch Bearbeitet.’’ 
* Redtenbacher’s Aceraius nikobaricus appears to me to be founded 
on an artifact having the hind parts of an Aceraius and the fore parts 
of a Tiberius. 
