Another cause of colic is suggested by Bokai[9]--namely, hypersensibility of the intestinal nerves--and he cites as evidence the diminution in pain produced by the administration of morphine; and it is not improbable that some hypersensibility of the nervous system of the intestine goes hand in hand with the vaso-constriction that has been shown to exist, while, in addition, many observers have found degenerative and even subacute inflammatory changes in the sympathetic nervous system of the abdomen, mainly in the splanchnic area and the solar ganglion. The action of vaso-dilator drugs on the pain of colic demonstrates the close association of vaso-motor changes with the acute paroxysmal pain. Riegels[10] investigated the cause of colic in 200 cases. He found that in every instance there was reason to suppose that toxic vaso-constriction of the vessels in the splanchnic area, due to irritation in the vaso-constrictor nerves, was brought about by the action of lead. Definite gastritis has also been described in some way simulating that caused by arsenic, with thickening in the submucosa of the stomach and intestine. Associated with this enteritis is endarteritis, atrophy of the glands, and Lieberkühn’s follicles. In the colon as well as the ileum was a well-marked enteritis involving the muscular lesions of the gut. Various other authors describe degenerative processes with cirrhotic changes in the gastro-intestinal tract. Amongst these, Galvini[11] describes, in a case of death from very chronic lead poisoning, extreme cachexia, perihepatitis, perisplenitis, atrophy of the stomach, liver, and spleen, and chronic sclerosing peritonitis (saturnine peritonitis). Associated with general changes in the abdominal cavity, marked inflammation and sclerosis was found in the solar plexus. There is said to be a very considerable correspondence between the condition of the peritoneal cavity and its contents in lead poisoning and barium poisoning. In some of the animals referred to in the description of the experiments, marked inflammatory conditions of the small intestines and colon were found, and in not a few instances definite ulceration and signs of recent hæmorrhages were found scattered along the intestinal tract. No sclerosis was found, however, in the peritoneal cavity, though a common symptom of all the animals, whether poisoned by inhalation, inoculation, or feeding, was the absence of practically all fat from the peritoneal cavity, the omentum being represented by an exceedingly thin membrane without any traces of fat whatever. =Nervous System.=--Perhaps the oldest classical symptom of lead poisoning is the potter’s palsy or wrist-drop due to interference with the nerve-supply of the extensor muscles of the hand, leading to inability to extend the wrist or the fingers on the arm, wasting of the affected extensor muscles, and finally a claw-shaped hand due to contractions produced by the pull of the unopposed flexor groups.