Fig. 16. Section behind the pharynx through the œsophagus.
b.c. Body-cavity. C. Cutis. c.b.c. Central compartment of body-cavity. c.g. Supra-œsophageal ganglia. c.m. Layer of circular muscles. co. Commissure between ventral nerve-cords. co. 2. Second commissure between the ventral nerve-cords. co1. 2. Mass of cells developed on second commissure (probably sensory). c.s.d. Common duct for the two salivary glands. d.l.m. Dorsal longitudinal muscles of pharynx. d.o. Muscles serving to dilate the opening of the pharynx. Ep. Epidermis. e.n. Nerve passing outwards from ventral nerve-cord. H. Heart. i.j. Inner jaw. j.p. Jaw papillæ. L. Lips of buccal cavity. l.b.c. Lateral compartment of body-cavity. le. Rod-like cuticular continuation of inner jaw, lying in a pit of the buccal cavity. l.m. Bands of longitudinal muscles. M. Buccal cavity. M1. Median backward continuation of buccal cavity. m.l. Muscles of jaw lever. m.s. Muscular sheets passing from side walls of pharynx to dorsal body-wall. œ. Œsophagus. œs.co. Œsophageal commissures. o.j. Outer jaw. ph. Pharynx. s.d. Salivary duct. s.g. Salivary gland. sl.d. Reservoir of slime gland. sy. Sympathetic nerves running in muscles of tongue or pharynx. sy1. Origin of sympathetic nerves to pharynx. T. Tongue. v.c. Ventral nerve-cords.
Figs. 17, 18. Two longitudinal horizontal sections through the head of Peripatus capensis. Fig. 17 is the most ventral. They are both taken ventral to the cerebral ganglia. In Fig. 17 dorsal tracheal pits are shewn with tracheæ passing off from them. (Zeiss a a, Hartnack's camera.) C. Cutis. c.s.d. Common salivary duct. ep. Epidermis. i.j. Inner jaw. M. Buccal cavity. M1. Median backward diverticulum of mouth. o.j. Outer jaw. s.d. Salivary ducts. T. Tongue. t. Teeth on tongue. tr. Tracheæ. tr.p. Tracheal pits.
Plate 50.
Fig. 19. "A, B, C, D, E, F, G." Seven transverse sections illustrating the structure of the supra-œsophageal ganglia. (Zeiss A, Hartnack's camera.) a. Dorso-lateral horn of white matter. b. Ventro-lateral horn of white matter. c. Postero-dorsal lobe of white matter. d. Ventral protuberance of brain. e. Central lobe of white matter. o.p. Optic ganglion.
“A. Section through anterior portions of ganglia close to the origin of the antennary nerve. B. Section a little in front of the point where the two ganglia unite. C. Section close to anterior junction of two ganglia. D. Section through origin of optic nerve on the right side. E. Section shewing origin of the optic nerve on the left side. F. Section through the dorso-median lobe of white matter. G. Section near the termination of the dorsal tongue of ganglion cells.”
Plate 51.
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-œsophageal ganglion and œsophageal 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 (sy1) arising from the ventral surface of the hinder part.