PLATE 1 
EXPLANATION OF FIGURES 
1 Lateral view of head of Chlamydoselachus anguineus. 4. 
2 Front view of same, with mouth forced widely open. X 3. 
ABBREVIATIONS 
ala, antero-lateral nasal aperture 
ama, antero-mesial nasal aperture 
a process a of ala nasalis 
a’ process a’ of ala nasalis 
8 process of 6 of ala nasalis 
lag, line of angle of gape 
lfd, labial fold 
mple, mandibular preangular labial 
crease 
nbg, naso-buccal groove 
nfd, nasal fold 
nfl, nasal flap 
nfr, nasal frill 
nlfd, naso-labial fold 
pag, primary angle of gape 
pla, postero-lateral nasal aperture 
pll, primary lower lip 
pma, postero-mesial nasal aperture 
pml, premaxillary lip 
pul, primary upper lip 
sag, secondary angle of the gape 
sll, secondary lower lip 
smf, supramandibular furrow 
smfd, supramandibular fold 
smafd, supramaxillary fold 
ssll, supplementary secondary lower lip 
ssul, supplementary secondary upper 
lip 
sul, secondary upper lip 
tag, tertiary angle of the gape 
tul, tertiary upper lip 
vp, valvular process 
198 
