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muscles of the palps are arranged in pairs, each composed of a flexor 
and an extensor, one of which is related to each article of the appendage. 
These muscles are attached at their bases to the wall of the article 
immediately proximal to that in which they find their insertion, the 
terminal article thus receiving only the insertion of the muscles which 
are contained within the third article. 
Like the palps, the musculature of the legs consists of a pair of 
muscles, of opposing action, related to each article. The only muscles 
originating from the dorsal integument are those, the lower extremities 
of which are inserted into the coxae. Of these, the adductors of the 
doxae (m. add. cx. 1-4) form an inner series of four stout muscles, one of 
which is attached to the mesial surface of the proximal margin of the 
article. The abductors of the coxae (to. abd. cx. 1-4) form an outer 
series, and are inserted in a corresponding position on the lateral part of 
the coxae. These coxal muscles, four pairs on each side of the body, 
take their origin from a series of moderately large discs which occupy 
the lateral fields of the anterior half of the body, lying between the 
closely crowded small marginal discs and the large discs which it has 
already been shown are associated with the capitular muscles. The 
integumental discs from which the coxal muscles originate, correspond 
to the three pairs of short grooves which are generally present on the 
antero-lateral parts of the dorsal surface of the body of female Ixodidae, 
while in the males of ornate species, the place of these grooves is taken 
by the lateral spots. For fuller information on this point the reader is 
referred to the work of Donitz 1 . The coxae contain within themselves 
a pair of muscles, the flexors and extensors of the succeeding article of 
the leg—the trochanter (m.f. tch. 1-4 and to. e. tch. 1-4)—and similarly, 
each successive article of the leg contains the flexor and extensor muscle 
which operates on the next succeeding article ; the last pair of muscles, 
situated in the tarsal article, terminates in a pair of long tendons which 
pass through the caruncle to find their insertions in the pulvillium. 
(c) The Muscles of the Alimentary Canal. 
Under this category are included— (a) the pharyngeal muscles, 
(b) the muscles of the oesophagus and the wall of the stomach with its 
coecal appendages, and (c) the anal muscles — all of which have been 
more or less completely dealt with in Part II of this paper in connection 
with the general anatomy of the alimentary canal (pp. 222-241). 
1 Donitz, W. (1909). 
