Fig.1 Ventral view of the roof of the branchial chamber of Chlamydoselachus 
anguineus after the lining membrane of the chamber has been removed, showing 
the pharyngobranchials, efferent branchial arteries and interarcuales dorsales 
muscles in natural position. 
ABBREVIATIONS 
cc, common carotid artery 
Coe, constrictor of the cesophagus 
ea.l, efferent branchial artery of first 
branchial arch 
ea.lI, efferent branchial artery of sec- 
ond branchial arch 
EB II, epibranchial of second branch- 
chial arch 
EPB.VI, epi-pharyngobranchial of 
sixth branchial arch 
HMD, hyomandibula 
Iad. IV, M.interarcualis dorsalis be- 
tween arches [V-V 
Iad.hy, M.interarcualis dorsalis be- 
tween arches hy-I 
lda, lateral dorsal aorta 
lmh, ligamentum mandibulo-hyoideum 
n, cut ends of nerves to tissues of roof . 
of branchial chamber 
PB.I, pharyngobranchial of first bran- 
chial arch 
PB.IV, pharyngobranchial of fourth 
branchial arch 
Rabd, retractor arcuum branchialium 
dorsalis 
Ssp, subspinalis muscle 
tiad, ligamentous sheet formed by ten- 
dons of Mm. interarcuales dorsales 
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