_a._ Anus. _ab._ Air-bladder. _ab´._ Aperture of air-bladder into throat.
_ac._ Anterior commissure. _af._ Anal fin. _al._ Alimentary canal. _ao._
Aorta. _ar._ Artery. _au._ Auditory pit. _b._ Brain. _bc._ Body-cavity.
_bd._ Bile duct. _bd´._ Aperture of bile duct into duodenum. _bl._
Coalesced portion of segmental ducts, forming urinogenital bladder. _bra._
Branchial arches. _brc._ Branchial clefts. _c._ Pyloric caæca. _c´._
Apertures of caæca into duodenum. _cb._ Cerebellum. _cdv._ Cardinal vein.
_ce._ Cerebrum: in figs. 47A and B, anterior lobe of cerebrum. _ce´._
Posterior lobe of cerebrum. _cf._ Caudal fin. _cn._ Centrum. _ch._
Choroidal fissure. _crv._ Circular vein of vascular membrane of eye. _csh._
Cuticular sheath of notochord. _cv._ Caudal vein. _d._ Duodenum. _dc._
Dorsal cartilage of neural arch. _df._ Dermal fin-rays. _dl._ Dorsal lobe
of caudal fin. _dlf._ Dorsal fin. _e._ Eye. _ed._ Epidermis. _ep._
Epiblast. _fb._ Fore-brain. _fe._ Pyriform bodies surrounding the zona
radiata of the ovum, probably the remains of epithelial cells. _gb._
Gall-bladder. _gd._ Genital duct. _gl._ Glomerulus. _gr._ Genital ridge.
_h._ Heart. _ha._ Hæmal arch. _hb._ Hind-brain. _hc._ Head-cavity. _hpd._
Hepatic duct. _hm._ Hyomandibular cleft. _hop._ Operculum. _hy._ Hypoblast;
in fig. 10, hyoid arch. _hyl._ Hyaloid membrane. _ic._ Intercalated
cartilaginous elements of the neural arches. _in._ Infundibulum. _ir._
Iris. _is._ Interspinous cartilage or bones. _iv._ subintestinal vein.
_ivr._ Intervertebral ring of cartilage. _k._ Kidney. _l._ Lens. _lc._
Longitudinal canal, formed by union of the vasa efferentia. _lin._ Lobi
inferiores. _ll._ Ligamentum longitudinale superius. _lr._ Liver. _lt._
Lateral line. _ly._ Lymphatic body in front of kidney. _m._ Mouth. _mb._
Mid-brain. _mc._ Medullary cord. _mel._ Membrana elastica externa. _mes._
Mesorchium. _mn._ Mandible. _md._ and _mo._ Medulla oblongata. _ms._
Mesoblast. _na._ Neural arch. _na´._ Dorsal element of neural arch. _nc._
Notochord. _nve._ Network formed by vasa efferentia on inner face of
testis. _od._ Oviduct. _od´._ Aperture of oviduct into bladder. _ol._ Nasal
pit or aperture. _olf._ Olfactory lobe. _op._ Optic vesicle. _op ch._ Optic
chiasma. _opl._ Optic lobes. _op th._ Optic thalami. _or ep._ Oral
epithelium. _ov._ Ovary. _p._ Pancreas. _pc._ Pericardium. _pcf._ Pectoral
fin. _pch._ Pigmented layer of choroid. _pf._ Peritoneal funnel of
segmental tube of mesonephros. _pfp._ Peritoneal funnel leading into
pronephric chamber. _pg._ Pectoral girdle. _plf._ Pelvic fin. _pn._ Pineal
gland. _po._ Primitive germinal cells. _pr._ Mesoblastic somite. _prc._
Pronephric chamber. _prn._ Pronephros. _pr n´._ Opening of pronephros into
pronephric chamber. _pt._ Pituitary body. _py._ Pyloric valve. _pz._
Parietal zone of blastoderm. _r._ Rostrum. _rb._ Rib. _rc._ Rectum. _s._
Spleen. _sc._ Seminal vessels passing from the longitudinal canal into the
kidney. _sd._ Suctorial disc. _sg._ Segmental or archinephric duct. _sgt._
Segmental tubules. _sh._ Granular outer portion of the sheath of the
notochord in the vertebral regions. _smx._ Superior maxillary process.
_snc._ subnotochordal rod. _so._ Somatic mesoblast. _sp._ Splanchnic
mesoblast. _spn._ Spinal nerve. _spv._ Spiral valve. _st._ Stomach. _st._
Seminal tubes of the testis. _sup._ Suctorial papillæ. _t._ Testis. _th._
Thalamencephalon. _thl._ Lobes of the roof of the thalamencephalon. _tr._
Trabeculæ. _ug._ Urinogenital aperture. _v._ Ventricle. _ve._ Vasa
efferentia. _vh._ Vitreous humour. _vl._ Ventral lobe of the caudal fin.
_vmt._ Ventral mesentery. _vn._ Vein. _vs._ Blood-vessel. _vsh._ Vascular
sheath between the hyaloid membrane and the vitreous humour. _vth._ Vesicle
of the thalamencephalon. _x._ Groove in epiblast, probably formed in
process of hardening. _y._ Yolk. _z._ Commissure in front of pineal gland.
_zr._ Outer striated portion of investing membrane (zona radiata) of ovum.
_zr´._ Inner non-striated portion of investing membrane of ovum. I.
Olfactory nerve. II. Optic nerve. III. Oculomotor nerve. V. Trigeminal
nerve. VIII. Facial and auditory nerves.