PLATES 
ABBREVIATIONS 
Arc.vsc.1—-6, visceral arches 1-6 
ar’ent., archenteron 
brs.vsc.1—6, visceral pouches 1-6 
cd., chorda dorsalis 
cl.n’bl., neuroblastic cell 
d.r., dental ridge 
ec’drm., ectoderm 
en’drm., entoderm 
fil.br., branchial filaments 
fis.vsc.1-6, visceral clefts 1-6 
gl.th., thyroid gland 
hyp., hypophysis 
vfb., infundibulum 
m., mouth 
m.pl., mouth plate 
mand., mandibular cartilage 
n’v., nerve 
olf., olfactory pit 
ph., pharynx 
pl.sc., placoid scale 
sp., spiracle 
st.germ., stratum germinativum 
t.b., taste-bud 
t.pap., taste papilla 
tb.n., neural tube 
vil.oes., oesophageal villi 
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