204 
ME. W. K. PAEKEE ON THE STEUCTUEE AND 
Explanation op Abbreviations. 
al.n. alinasal. 
al.s. aliseptal. 
al.s. alisphenokl. 
ar. articular. 
ar.c. articular condyle. 
a. sc. anterior semicircular canal. 
an. auditory sac (periotic mass). 
a. t. annulus tympanicus. 
ail. atlas. 
b. br. basibranchial. 
b. h. basihyal. 
b. t. basitemporal processes. 
hr. branchial arch. 
ct. cutaneous system. 
c. a.t. cartilaginous annulus tympanicus. 
c. br. cerato-branchial. 
cl. 1 . 1st cleft. 
c. p. claspers. 
Cl. 1st cerebral vesicle. 
C 1". rhiuencephalon. 
C I s . prosencephalon. 
C l c . dcutencephalon. 
C 2. mesencephalon, or middle cerebral vesicle. 
C 3. 3rd cerebral vesicle. 
cr. cranium. 
c.tr. cornu trabeculae.. 
cl. dentary. 
dr. derm. 
e. eyeball. 
e.br. epibranehial. 
e.bra. external branchiae. 
c.n. external nostril. 
ep. epiotic. 
e.pa. ethmo-palatal. 
e. st. extrastapedial. 
eth. ethmoid. 
/. frontal 
f. f. fenestral fossa. 
/.m. facial muscle. 
f.m.x. facial plate of maxillary. 
f.n. fronto-nasal process. 
fo. fontanelle. 
f.r. fenestra rotunda. 
f.s.o. fenestra ovalis. 
f.w. facial wall. 
g.l.t. gelatinous tissue. 
li.br. hypobranchial. 
h.c. hyaline cartilage. 
h. h. hypohyal. 
li.m. hyo-mandibular. 
li.se. horizontal semicircular canal. 
hy. hyoid. 
hy.h. hypohyal. 
i. br. internal branchiae. 
i.f.st. infrastapedial. 
i.h.m. infra-hyomandibular. 
i.n. internal nostril. 
inf. infundibulum. 
it. st. interstapedial. 
iv. investing mass. 
iv.c. investing-mass connective. 
i.v.p. inner valvular process. 
1. labyrinth. 
l. d.g. lower dentigerous plate. 
IX. lower labial. 
ip. lips. 
l. t. labial teeth. 
lx. larynx. 
m. mouth. 
m.c. membranous cranium. 
m. d. digastric muscle. 
mlc. Meckel’s cartilage. 
m.mlc. mento-meckelian. 
m.ob. medulla oblongata. 
m. p.g. metapterygoid. 
m.p.g.c. metapterygoid connective. 
m.s. medulla spinalis. 
mx. maxillary. 
n. nasal. 
nc. notochord. 
no. notch. 
n. p.x. nasal process of premaxillary. 
ox. occipital condyles. 
ol. olfactory sac, or tube. 
o.l. C 2. optic lobes. 
op. opisthotic. 
op.rn. operculum. 
op.o. opercular opening. 
op.p. opercular process. 
or.p. orbitar process. 
