STRUCTURE AND DEVELOPMENT OE LEPIDOSTEUS. 
435 
Ir. 
Liver. 
It . 
Lateral line. 
tu¬ 
Lymphatic body in front of 
kidney. 
rn. 
Mouth. 
m.b. 
Mid-brain. 
m.c. 
Medullary cord. 
m.el. 
Membrana elastica externa. 
mes. 
Mesorchium. 
mn. 
Mandible. 
md. and mo. Medulla oblongata. 
ms. 
Mesoblast. 
n.a. 
Neural arch. 
n.a. 
Dorsal element of neural arch. 
no. 
Notochord. 
n.v.e. 
Network formed by vasa effe- 
rentia on inner face of testis. 
od. 
Oviduct. 
od'. 
Aperture of oviduct into bladder. 
61. 
Nasal pit or aperture. 
olf. 
Olfactory lobe. 
op. 
Optic vesicle. 
op.ch. 
Optic chiasma. 
op.l. 
Optic lobes. 
op.th. 
Optic thalami. 
or.ep. 
Oral epithelium, 
ov. 
Ovary. 
p. 
Pancreas, 
pc. 
Pericardium. 
pc.f. 
Pectoral fin. 
p.ch. 
Pigmented layer of choroid. 
pf 
Peritoneal funnel of segmental 
tube of mesonephros. 
p-f-p- 
Peritoneal funnel leading into 
pronephric chamber. 
P-9- 
Pectoral girdle. 
P J f 
Pelvic fin. 
pn. 
Pineal gland. 
p.o. 
Primitive germinal cells. 
pr. 
Mesoblastic somite. 
pr.c. 
Pronephric chamber. 
pr.n. 
Pronephros. 
pr.n'. 
Opening of pronephros into pro¬ 
nephric chamber. 
pt. 
Pituitary body. 
py. 
Pyloric valve. 
p.z. 
Parietal zone of blastoderm. 
r. 
Postrum. 
rb. 
Pib. 
re. 
Pectum. 
s. 
Spleen. 
s.c. 
Seminal vessels passing from the 
longitudinal canal into the 
kidney. 
s.d. 
Suctorial disc. 
sg. 
Segmental or archinephric duct. 
sg.t. 
Segmental tubules. 
sh. 
Granular outer portion of the 
sheath of the notochord in the 
vertebral regions. 
s.mx. 
Superior maxillary process. 
s.nc. 
Sub-notochordal rod. 
so. 
Somatic mesoblast. 
sp. 
Splanchnic mesoblast. 
sp.n. 
Spinal nerve. 
sp.v. 
Spiral valve. 
st. 
Stomach. 
s.t. 
Seminal tubes of the testis. 
su.p. 
Suctorial papillae. 
t. 
Testis. 
th. 
Thalamencephalon. 
th.l. 
Lobes of the roof of the thala¬ 
mencephalon. 
tv. 
Trabeculae. 
u.g. 
Urinogenital aperture. 
V. 
Ventricle. 
v.e. 
Vasa efierentia. 
v.h. 
Vitreous humour. 
v.l. 
Ventral lobe of the caudal fin. 
v.mt. 
Ventral mesentery. 
vn. 
Vein. 
vs. 
Blood-vessel. 
