The nervous system consists of brain,Double ventral nervecord and ganglia and nerves.
The brain is formed of the supra pharyngeal ganglia and is a bilobed mass of nervous tissue situated on the dorsal wall of the pharynx in 3rd segment.The ganglia found below the pharynx in the 4th segments is called the subpharyngeal ganglia. The brain and the subpharyngeal ganglia are connected by a pair of circum pharyngeal connectives.They run one on each side of the pharynx. Thus a nerve ring is formed around the anterior region of the alimentary canal. The double, solid ventral nerve cord runs backwards from the subpharyngeal ganglia, in the mid ventral line to the hind end of the body. The ventral nerve cord has segmental ganglion one in each segment.From the brain nerves are given off to the peristomium. From each ganglion of the ventral nerve cord, three pairs of nerves are given off to the body wall and other organs.
The brain is formed of the supra pharyngeal ganglia and is a bilobed mass of nervous tissue situated on the dorsal wall of the pharynx in 3rd segment.The ganglia found below the pharynx in the 4th segments is called the subpharyngeal ganglia. The brain and the subpharyngeal ganglia are connected by a pair of circum pharyngeal connectives.They run one on each side of the pharynx. Thus a nerve ring is formed around the anterior region of the alimentary canal. The double, solid ventral nerve cord runs backwards from the subpharyngeal ganglia, in the mid ventral line to the hind end of the body. The ventral nerve cord has segmental ganglion one in each segment.From the brain nerves are given off to the peristomium. From each ganglion of the ventral nerve cord, three pairs of nerves are given off to the body wall and other organs.
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