290 
A ccmth ia lectularia 
being very rugose with parallel furrows whose length is almost at right 
angles, to the length of the bug. On its anterior lateral angles the 
mesosternum bears two spiracles. Their position is such that they 
are invisible from either the dorsal or ventral surface. The spiracles 
on the pro- and meso-thorax do not possess the “ wax ” bladders found 
on all the other respiratory openings. 
From above, the meta-thorax is inconspicuous and its dorsal por¬ 
tion, being covered by the wing cases, is puncture free, and carries no 
bristles. The pleura, in their sculpture, strongly suggest the Astrea 
type of coral, in that there are central larger depressions from which others, 
smaller ones, radiate and anastomose with those radiating from other 
central depressions. Besides this, it is greatly strengthened by a broad 
rib which divides the episternum of the meta-thorax from the epimeron 
of that segment. This rib is sculptured in a manner found nowhere 
else on the bed bug. The part of it near the metasternum is reticulated 
with a band of almond-shaped papillae whose length is along the band, 
while, towards the meta-notum, the reticulations take on a more or less 
polygonal form. Besides this the chitin of the edges here is greatly 
thickened. Ventrally the metasternum is conspicuous and has a con¬ 
siderable bulk, and thus it projects somewhat over the first abdominal 
segment (Fig. 29). This increased bulk has the effect of separating the 
coxal cavities which here, as on the segment immediately preceding, are 
well apart. In this space between the coxal cavities of the mesosternum 
is to be found an organ which, from a structural point of view, would 
appear to possess olfactory properties. It will be treated in detail later 
on, but here it may be said that it lies in a cavity which opens to the 
exterior by a pore in the middle line of the metasternum where it 
overhangs the first abdominal segment. This pore cannot be seen from 
the ventral surface. 
The legs of the bug are of the usual insect type and consist of coxa, 
trochanter, femur, tibia, and tarsus (Fig. 19). The latter is divided into 
three joints of which the first is the shortest and the third the longest. 
As previously mentioned, the legs are plentifully supplied with bristles 
of both kinds. The simple are found on the ventral surface of the 
tibiae, on their ends as well as on the tarsi, while the serrated occur on 
the outer edge and sides of the tibiae, on the femur, and on the tro¬ 
chanter. Besides these two kinds, the ends of the tibiae have, on their 
ventral surfaces, a dense brush formed of bristles of different lengths, so 
arranged that their tips continue the line of the ventral surface of the 
tibia, which is brought about by the longer ones having their tips greatly 
