. The Cambridge natural history. Zoology. 12 PERIPATUS largest part of the alimentary canal. It is a dilated soft-walled tube, and leads behind into the short narrow rectum (H), which opens at the anus. There are no glands opening into the alimentary canal. Nervous System. The central nervous system consists of a pair of supra- oesophageal ganglia united in the middle line, and of a pair of widely divaricated ventral cords, continuous in front with the Rupra-oesophageal ganglia (Fig. 9). Tlie ventral cords at first sight appear to be without gangli- onic thickenings, but on more careful examin
. The Cambridge natural history. Zoology. 12 PERIPATUS largest part of the alimentary canal. It is a dilated soft-walled tube, and leads behind into the short narrow rectum (H), which opens at the anus. There are no glands opening into the alimentary canal. Nervous System. The central nervous system consists of a pair of supra- oesophageal ganglia united in the middle line, and of a pair of widely divaricated ventral cords, continuous in front with the Rupra-oesophageal ganglia (Fig. 9). Tlie ventral cords at first sight appear to be without gangli- onic thickenings, but on more careful examination they are found to be enlarged at each pair of legs (Fig. 9). These enlarge- ments may he regarded as imperfect ganglia. There are, there- FlG. 9.—Brain and anterior part of the ventral nerve- cords of Peripatiis capensis enlarged and viewed from tLe ventral surface. (After Balfour.) The paired appendages (cZ) of the ventral surface of the brain are seen, and the pair of syraj^athetic jierves («?/) arising from the ventral surface of the hinder part. From the commencement of the oesopha- geal commissures pass off on each side a pair of nerves to the jaws (/»). 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 oif to the oral papillae a pair of large nerves on each side (mii). Behind this the cords present a series of enlarge- ments, one pair for each pair of feet, from wliich a pair of large nerves pass off on each side to the feet {pn). atii, Antennary nerves ; co, commissures between ventral cords ; d, ventral appendages of brain ; E, eye ; en, nerves passing outwards from ventral cord ; , ganglionic enlargements from which nerves to feet pass off; jn, nerves to jaws ; orfi, ganglionic enlargement from which nerves to oral papillae pass off; orn, nerves to oral papillae ; pc, posterior lobe of brain ; pn, nerves to feet
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
