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Previous Observations on Efferent Vesical Fibres'.As we shall deal almost exclusively with the efferent nerves of the bladder, we omit reference to previous work on its rhythmic contraction, its internal pressure, its afferent nerves2, and restrict our account of the earlier observations to those which relate to the origin from the spinal cord of the efferent bladder fibres and the course these fibres take.First as to the upper set of nerves. Gianuzzi, experimenting after the manner of Budge, found that contraction of the bladder in the dog was obtained by pricking the spinal cord at the level of the lower part of the 3rd lumbar vertebra, and that the contraction usually ceased on section of the nerves called later the hypogastric nerves; sometimes in order to stop the effect it was necessary to cut also strands said to run to the bladder from the upper sacral sympathetic ganglia. He concluded that motor fibres ran to the bladder from the lumbar spinal cord, traversing on their way the sympathetic chain and the inferior mesenteric ganglia. The argument is not quite satisfactory, since the absence I Budge. Virchowv's Archiv, xv. 115. 1858. Gianu z zi. Journ. de la Physiol., VI. of effect might be due to the progressive decrease in irritability which takes place in the spinal cord after exposure; this explanation seems to be the one adopted by Budge. Sokownin made observations of a similar nature to those of Gianuzzi but did not describe any fibres as passing from the lurnbar cord to the bladder except by the hypogastric nerves. He advanced a step by showing that stimulation of the cut peripheral ends of the hypogastric nerves causes contraction of the bladder. H. Nussbaum confirmed Sokownin except that he found that some fibres continued on in the sympathetic chain. This was a return to Gianuzzi's view but with less definiteness as to the course taken by the fibres. Langley stimulated the sympathetic chain from above downwards, taking precautions against reflexes from the spinal cord; he found in the rabbit contraction of the bladder on stimulating the sympathetic from about the 2nd to the 6th lumbar ganglia; indicating that the motor fibres of the bladder arise from about the 1st to the 5th lumbar nerves. The branches from the sympathetic to the inferior mesenteric ganglia also gave contraction. Nav rocki and Sk abitschewsky stimulated in the cat the lumbar nerves in the vertebral canal and found contraction of the bladder from the 4th and 5th lumbar nerves. They found no effect after section of the hypogastric nerves, and no effect on stimulating the sympathetic a little above the sacral region. Sherrington, in the cat found contraction of the bladder on stimulating the 3rd lumbar nerve, as well as the 4th and 5th, and in two cases out of seven, he obtained a slight effect also on stimulating the 2nd lumbar nerve. In the monkey he obtained contraction from the 2nd, 3rd and 4th lumbar in eight cases, and from the 3rd, 4th and 5th in one case. It will be seen, that the points which require further elucidation ...

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Lower or sacral set of Nerve Fibres in the rabbit. Function, p. 85. Origin, p. 90. Lower or sacral set of Nerve Fibres in the cat, p. 92. Course of the Nerve Fibres from the Spinal Cord to the Periphery, and Nature of Effects produced by stimulating the different peripheral Nerves. Peripheral Fibres of upper set in the rabbit, p.

IN a former Paper IP have given an account of some observations on the origin fronm the spinal cord of the nerve fibres which are present in the cervical sympathetic, and of the peripheral distribution of the fibres derived from each spinal nerve. These observations-which in part confirmed and in part extended the results of others-showed that in the cat the first seven thoracic nerves sent nerve fibres to the cervical sympathetic; that the fibres of each nerve had its characteristic distribution. Thus the 1st thoracic nerve supplied the pupil and the nictitating membrane but sent few or no fibres to the vessels of the ear, and none to the hairs of the face and neck; the 2nd thoracic differed from the 1st in sending a considerable number of fibres to the blood vessels of the ear, and as a rule in sending more fibres to the nictitating membrane and fewer to the pupil; the 3rd thoracic sent a few fibres only to the puipil; the 4th thoracic sent none to the pupil, a few only to the nictitating membrane, but as a rule sent a few to the hairs of the face and neck; the 5th also sent no fibres to the pupil, very few and sometimes none to the nictitating membrane, but some to the vessels of the ear and to the hairs of the face and neck. The 6th and 7th thoracic supplied the hairs only, the 6th sending more fibres to them than the 7th.There is good ground for believing that all these fibres of the cervical sympathetic terminate in the superior cervical ganglion, the impulses they normally convey passing to the nerve-cells of the ganglion and so to the nerve-fibres given off by the cells.Suppose now that the cervical sympathetic is cut, and the ends are placed together. Presumably the cut peripheral fibres will regenerate. If they do, will they grow past the superior cervical ganglion, and form 1