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but on account of their close relationship with the genital canal, their 
description is deferred to the section dealing with the genital muscles. 
The remaining body-muscles differ from the foregoing in the fact 
that they are not connected in any way with the dorsal integument. 
They form two series—the subcoxcd viuscles and the intercoxal muscles. 
The superior stibcoxctl muscles (m. sub. cx. s .) form a broad band of 
parallel bundles which run transversely across the floor of the body- 
cavity on either side of the median line, immediately posterior to the 
last pair of coxae and the spiracles. The inner extremities of the 
muscle bundles are attached to the ridge in the ventral integument 
formed by the coxal fold, and their outer extremities are inserted along 
the posterior portion of the supracoxal fold. 
The inferior subcoxcd muscles ( m. sub. cx. i) are composed of bundles 
of much shorter length than the preceding, which bridge across the 
depression of the ventral body wall formed by the coxal folds. The 
series commences at the level of the third pair of coxae and extends 
backwards for some distance beneath the superior subcoxal muscles. 
The inter coxed muscles form two groups—the latercd and the mesial. 
The latercd intercoxcd muscles (m.l.int.cx. 1 and 2), two in number on 
either side, connect the supracoxal fold with the first and second coxal 
interspaces respectively. The mesial intercoxcd (to. to. int. cx. 1-2) muscles 
are attached at their inner extremities to a centrally situated chitinous 
plate—the endosternite — from the lateral margins of which, five slips of 
muscle diverge. Of these, the first passes to the interspace between 
the basis capituli and the first pair of coxae, the second, third and fourth 
are inserted into the three coxal interspaces respectively, and the fifth 
finds its distal attachment on the posterior margin of coxa 4. 
(b) The Muscles of the Appendages. 
These include the muscles of the capitulum and those of the legs. 
Two pairs of muscles are attached to the basis capituli. The 
depressor muscles of the capitulum (to. d. c.) consist of two stout bundles 
which originate from a pair of conspicuous integumental discs of large 
size and elliptical contour situated at the level of the anterior fourth of 
the dorsal surface of the body (see Text-fig. 2). From their points of 
origin, each muscle passes downwards and forwards and is inserted into 
the lateral portion of the postero-ventral margin of the basis capituli. 
The second pair, the levator muscles (to. 1 . c.) of the capitulum, are some¬ 
what smaller than the preceding; they originate from one of a series of 
