Fig. 20. Portion of a transverse section through the hinder part of
_Peripatus capensis_ (male). The section passes through a leg, and shews
the opening of the segmental organ (_o.s._), and of a crural gland,
_o.f.g._, and the forward continuation of the enlarged crural gland of the
17th leg (_f.gl._). (Zeiss a a, Hartnack's camera.) _a.g._ accessory gland
of male (modified crural gland of last leg). C. Cutis. _cl._ Claw. _cu._
Cuticle. _ep._ Epidermis. _f.gl._ Crural gland. _h._ Cells in lateral
compartment of body-cavity. _o.f.g._ Orifice of accessory foot gland.
_o.s._ Opening of segmental organ. P. Three spinous pads on ventral surface
of foot. _pr._ Prostate. R.M. Retractor muscle of claw. _s._ Vesicle of
nephridium. _s.c.i._ Region No. 1 of coiled part of nephridium. _sl.g._
Tubule of slime gland. _s.o.t._ Terminal portion of nephridium. _st._
Stomach. _st.e._ Epithelium of stomach. _v.c._ Ventral nerve-cord. _v.d._
Vas deferens.
Fig. 21. "Longitudinal vertical section through the supra-oesophageal
ganglion and oesophageal commissures of _Peripatus capensis_. (Zeiss a a,
Hartnack.)" _at._ Antenna. _e._ Central lobe of white matter. _j._ Part of
jaw. _s.g._ Salivary gland.
Fig. 22: drawn by Miss Balfour. Brain and anterior part of the ventral
nerve-cords of _Peripatus capensis_ enlarged and viewed from the ventral
surface. The paired appendages (_d_) of the ventral surface of the brain
are seen, and the pair of sympathetic nerves (_sy_{1}) arising from the
ventral surface of the hinder part.
From the commencement of the oesophageal commissures (_oes.co._) pass off
on each side a pair of nerves to the jaws (_j.n._).
The three anterior commissures between the ventral nerve-cords are placed
close together; immediately behind them the nerve-cords are swollen, to
form the ganglionic enlargements from which pass off to the oral papillæ a
pair of large nerves on each side (_or.n._).
Behind this the cords present a series of enlargements, one pair for each
pair of feet, from which a pair of large nerves pass off on each side to
the feet (_p.n_). _at.n._ Antennary nerves. _co._ Commissures between
ventral cords. _d._ Ventral appendages of brain. E. Eye. _e.n._ Nerves
passing outwards from ventral cord. _F.g._ Ganglionic enlargements from
which nerves to feet pass off. _j.n._ Nerves to jaws. _or.g._ Ganglionic
enlargement from which nerves to oral papillæ pass off. _or.n._ Nerves to
oral papillæ. _p.c._ Posterior lobe of brain. _p.n._ Nerves to feet. _s.y._
Sympathetic nerves.
Fig. 23. "Longitudinal horizontal section through the head of _Peripatus
capensis_, shewing the structure of the brain, the antennary and optic
nerves, &c. (Zeiss a a, Hartnack's camera.)" _at._ Antenna. _at.n._
Antennary nerve. _cor._ Cornea. _e._ Central mass of white matter. _l._
Lens. _op.n._ Optic nerve. _ph._ Pharynx. _p.p._ Primary papilla covered
with secondary papillæ and terminating in a long spine. _sy._ Pharyngeal
sympathetic nerves.
Fig. 24. "Eye of _Peripatus capensis_, as shewn in a longitudinal
horizontal section through the head. The figure is so far diagrammatic that
the lens is represented as filling up the whole space between the rods and
the cornea. In the actual section there is a considerable space between the
parts, but this space is probably artificial, being in part caused by the
shrinkage of the lens and in part by the action of the razor. (Zeiss C,
Hartnack's camera.)" (It appears that the ganglionic region of the eye is
covered by a thin capsule, which is omitted in the figure.)
_cor._ Cornea. _l._ Lens. _op._ Optic ganglion. _op.n._ Optic nerve.
_pi.r._ Pigment. _Re._ rods. _s.p._ Secondary papillæ.
Fig. 25. Longitudinal horizontal section through the dorsal skin, shewing
the peculiar arrangement of the circular muscular fibres. (Zeiss A,
Hartnack's camera.)