SEXUAL REFLEXES. 851 



are expelled. 1 Tampons of cotton-wool introduced into the rectum excite their 

 own expulsion, if they be relatively large. The expulsion is accompanied by 

 movements of both hind-limbs and tail. When the level of transection 

 lies above the sciatic plexus, excitation with smaller tampons, or by electrodes 

 applied just within the anus, evokes a complete act of defalcation. The 

 posterior end of the body is raised on the extended hind-limbs, the tail 

 is raised, and after expulsion of the material from the rectum follow move- 

 ments of nettoyage by the hind-limbs. Defalcation, in the sense of regular 

 expulsion of faecal matter, occurs without difficulty in mammals after tran- 

 section in the upper lumbar region, or higher. The external sphincter is 

 patulous in some cases for a few hours or days after the spinal transection, 

 but more usually recovers tone a few minutes after the operation, or never 

 loses it. Goltz and Ewald found the tonus return even after exsection of 

 the lumbosacral region of the cord. The rhythmic contractions of the 

 sphincter noted 2 to set in after high lumbar spinal transection in the dog, 

 can be inhibited by strong sensory stimuli of adjacent parts. 3 Gowers, 4 in 

 describing the condition of the rectal sphincter in disease of the spinal 

 cord, says two states can be distinguished by introduction of the finger. If 

 the lumbar centre is inactive, there is a momentary contraction, due to local' 

 stimulation of the sphincter, and then a permanent relaxation. If, however, 

 the reflex centre and motor nerves from it are intact, the introduction of the 

 finger is followed " first by relaxation and then by gentle, firm, tonic contraction. 

 I have verified this by introducing an india-rubber cylinder instead of the 

 finger, and registering the pressure on the cylinder by connecting it with 

 a recording apparatus. The relaxation is then found to be preceded by a very 

 slight brief contraction, and to be followed by unbroken tonic contraction." 

 The relaxation may also be readily produced by stimuli to the mucous 

 membrane above the sphincter. Incontinentia alvi is described as usual in 

 man after total transverse lesion of the cord ; it is not at all usual in the 

 monkey. 



Sexual reflexes. — The uterus. — As is well known, uterine contractions 

 may be induced by applying heat or cold to the abdomen, by passing a 

 catheter, by hot or cold rectal injections, by drawing back the perineum, or by 

 putting the child to the breast. In animals, such contractions are strongly 

 excited by faradisation of the central end of the first sacral nerve. 5 As the 

 irritation in these instances is not applied to the uterine tissue or to efferent 

 nerve channels, the resultant uterine reactions must be induced reflexly. 

 Rohrig b states that asphyxia does not produce uterine contractions or abortion 

 if the lumbar region of the spinal cord is destroyed, although it does 

 produce those events if the cord is cut across in the thoracic region. Cases 

 have been from time to time reported in which parturition has occurred 

 and run its course in normal fashion in paraplegic women, the inter- 

 ruption of the cord being complete, and as low as the tenth thoracic level. 

 Marshall Hall argued from such instances that uterine action is a reflex spinal 

 one connected with a lumbar "centre." In these cases parturition is, of 

 course, unattended with pain, although the labour " pains " are strong and 

 efficacious. In one case, during the second stage, the " pains " recurred about 

 every two minutes, each lasting about forty-five seconds. The patient 

 perspired after each pain, as if she had been exerting herself. There was an 

 indistinct tight feeling referred to the epigastrium at the height of each pain ; 



1 A. Bickel, Rev. mid. de la Suisse rom., Geneve, 1897 ; J. Ott, Journ. Physiol., Cam- 

 bridge and London, 1879, vol. ii. p. 54. 



2 Gluge, Bull. Acad. roy. d. sc. de Belg., Bruxelles, 1868 ; Goltz, Arch. f. d. gcs. 

 Physiol., Bonn, 1873, Bd. vii. S. 582. 



3 Goltz, loc. cit. ; J. Ott, loc. cit. 



4 "Diseases of the Nervous System," London, vol. i. 



5 Cyon, Arch. f. d. gcs. Physiol., Bonn, 1874, Bd. viii. 



6 Virchow's Archiv, 1879, Bd. lxxvi. S. 1. 



