118 C¢. Ms Fo von" HAVEK 
and polished surface without any large punctures through all the intermediate 
stages to an ill-defined area in which the punctures are only very slightly less dense 
than on the rest of the underside. Species in which the females display this charac- 
teristic to a greater or lesser degree occur in the Palaearctic (e.g. murinus (Linnaeus), 
cinnamomeus (Candéze)), Oriental (e.g. binodulus (Motschulsky), setiger (Bates), 
hispidulus (Candéze)), Ethiopian (e.g. foedus (Candéze)) and Madagascan regions 
(e.g. vestitus Klug, cinctupes (Candéze)) and in North America (e.g. vectangularis 
(Say)) and Central America (e.g. paleatus (Champion)). The Northern Indian 
lutosus (Candéze) is unusual in that both the fourth and fifth visible abdominal 
sternites bear a polished patch in the mid line. The Madagascan species sinuatus 
(Candéze) differs from all other species known to me in that the last visible 
abdominal sternite of the female bears a single enlarged raised puncture from 
which a number of short slender scales arise. In appearance this raised puncture 
resembles those found on the fourth visible abdominal sternite of certain Australian 
species. 
Australian Agrypnus species differ from those from other regions in that the 
modified areas, where they occur, lie on the fourth, and in one species also on the 
third, visible abdominal sternite. A large raised area with a number of punctures 
is found in some species such as ursulus (Candéze) and Jaticollis (Candéze). The 
polished area is smaller but much more strongly raised and bears only two or three 
punctures in stigmosus (Blackburn) and poriginosus (Candéze). A single large 
raised puncture, from which several short narrow scales arise, occurs in a number 
of species including punctipennis (Candéze) and marmoratus (Candéze). A large 
single puncture of this kind is present on both the third and fourth visible abdominal 
sternite of adustus (Elston). The function of these pores and patches is unknown. 
The antennae of the male are considerably larger and more strongly serrate than 
those of the female in the Indian tvuncatus (Herbst) and probably also the 
Australian gracilis (Blackburn) of which only the male is known. 
Sexual dimorphism of the tarsal segments is known in only one species, obscurus 
Fleutiaux from Africa (= abstrusus see p. 120). In this species the fourth tarsal 
segment of the male is distinctly lobed while that of the female is only obliquely 
truncate. 
DISTRIBUTION. Agrypnus species have been recorded from all parts of the 
world except South America. The largest number of species has been described 
from the Oriental and Australian regions. 
BIOLOGY AND HABITS. Hardly anything has been published on the habits of 
the adult beetles. Agrypnus murinus (Linnaeus) is generally recorded as living 
under stones and in the ground. A number of species have been taken from the 
foliage of sandal (Fleutiaux, 1933: 1). A. eucalypti (Blackburn) was found under 
the bark of Eucalyptus. Specimens in collections have provided no information 
other than having been taken by sweeping, beating or in light traps. Fleutiaux 
(1944 : 148) records that Compsolacon species were found together with Octocryptus 
coomant near lakes and rivers and in damp places. 
A great deal has been written on the Elaterid ‘clicking’ mechanism and the part 

