C. Hay Murray 
293 
under surface near to its outer edge and on the dividing line between 
the bristly rugose part and the shining smooth underlap. 
The first seven abdominal segments of the male bug are quite 
normal, but, in the female, on the ventral surface of segment four, and 
to the right of the median line, at the posterior edge of the segment, is 
found the opening to what is called the “ Organ of Berlese.” This is 
a round mass of a dull white colour lying in the body cavity at the right 
side. Under it is found a layer of fine chitinous rods, but what are 
the functions of the organ the writer hesitates to say, the authorities 
differing greatly on the subject. Berlese, its discoverer, says that its 
use is to enable the female to derive nutriment from excess of sper¬ 
matozoa received in copulation, while Ribaga infers from the presence 
of the chitinous rods, that it is a stridulating organ, although he comments 
on the peculiarity that it is found only in the female. 
The genital segments of the female bug are composed of pairs of 
chitinous plates which are well supplied with simple bristles. Following 
the sixth segment there are four plates, two of which, meeting in the 
middle line, form the vagina, which is a groove practically thatched 
with long whip-like simple bristles which interlace (Fig. 23). Outside 
these are a pair of plates one on either side, each bearing a spiracle, 
and being in all probability part at least of the seventh abdominal 
segment. 
The two central plates have their lateral edges strongly reflexed 
and thickened, evidently to secure strength. In shape they are approxi¬ 
mately quadrilateral except in the middle line, and at the posterior 
end, where they are prolonged into blunt points and thus separate the 
remaining pair of plates. These last are overlapped in part (portions 
A and B in Fig. 23) by the central plates, and at their anterior lateral 
edges meet the spiracle-bearing portions of the seventh segment. These 
overlapped plates are more or less quadrilateral, but in the middle line 
and posteriorly there is a large notch which leaves a space lined with 
delicate chitin and closed by an unpaired chitinous cap, often seen 
reflexed in specimens which have been mounted in balsam. This is 
where, the anus opens, and it would appear to be covered by this lid. 
Around the anus, as previously mentioned, the bristles are very long 
and all simple with the exception of those on the anal cap, and here 
they are all serrated. Segments six and seven have also a prepon¬ 
derance of the simple with the serrated at the edge. 
In the male there is a great asymmetry in the genital segments. 
The seventh is quite normal, but the following one, as shown in the 
