WORK UPON VISCERAL AND ALLIED NERVES. 55 



experiments do not disprove the statements of Fellner with 

 regard to the innervation of the rectum in the dog, they 

 only suggest that further observations are desirable." 



We should note, however, that GaskelP "entirely en- 

 dorses " Fellner's conclusion. He obtained in the dogf 

 contraction of the longitudinal fibres of the rectum on 

 stimulation of the nervus erigens, while, when the hypo- 

 gastrics were stimulated, a distinct peristaltic contraction 

 was observed. In the frog, too, he showed that fibres 

 occurred in the seventh nerve, which, when stimulated, 

 caused contraction of the circular muscles, and that the 

 eighth and ninth nerves contained fibres stimulation of 

 which caused contraction of the longitudinal muscles and 

 pulling down of the rectum. 



Langley '^ describes the effect of stimulation of the fibres 

 of the upper region as inhibition of the descending colon 

 and rectum, sometimes preceded by a brief contraction. 

 The inhibition affects both longitudinal and circular fibres. 

 The set of fibres from the sacral region produce a strong 

 contraction of both sets of muscle. 



With regard to the spinal roots, through which these 

 two sets of fibres leave the cord, Bechterew and Mislawski^ 

 describe them as being the upper lumbar roots down to the 

 sixth or seventh, and also the third sacral. The whole 

 question has lately been closely gone into by Langley and 

 Anderson.* In the rabbit the roots are the second to fifth 

 lumbar inclusive, the third and fourth sacral, and, as a rule, 

 either the second sacral or the first coccygeal. In the cat 

 the second to fourth lumbar, the second and third sacral, 

 and either the fifth lumbar or the first sacral. In the dog 

 the origin of the lumbar fibres is slightly more anterior, and 

 that of the sacral slightly more posterior than in the cat. 

 The upper set of fibres in the rabbit causes, when stimu- 

 lated, inhibition of the intestinal muscles (circular and 

 longitudinal), sometimes a preliminary contraction which 



^ Jour 71. of Fhys., vol. vii., p. 26, 1885. 

 2 Ibid., vol. xii. ; Froc. Physiol. Soc, p. 23, 1890. 

 ^ Arch. f. {Anat. u.) Fhys., suppl., p. 243, 1889. 

 '^ Joiirn. of Phys., vol. xviii., p. 67, 1895. 



