WORK UPON VISCERAL AND ALLIED NERVES. 69 



striated genital muscles of the male. The upper set of 

 fibres leave the cord in the cat either in the third and fourth 

 lumbar with a few in the fifth, or in the fourth and fifth with 

 a few in the third, occasionally there are some in the second. 

 In the dog their origin is a litde more anterior, for there 

 are never any in the fifth. In the rabbit they pass out in 

 the third, fourth and fifth. Sherrington ^ observed contrac- 

 tion of the cremaster muscle on stimulation of the second 

 and third anterior roots of lumbar nerves in rhesus, in one 

 case the fourth lumbar was found to be effective instead of 

 the second. 



The posterior set. in the cat, are found in the first and 

 second, occasionally in the third sacral ; in the rabbit in the 

 second, third and fourth sacral anterior roots. Sherrington ^ 

 observed a sharp closure of the vaginal orifice on stimufation. 

 of the second and third sacral nerves in the cat, and in 

 rhesus. As a rule the third nerve was more effective than 

 the second, and the contraction was bilateral. 



The course of the upper set of fibres is by the white 

 rami to the sympathetic chain, whence they may travel by 

 two paths, either to the pudic nerve or via the pelvic plexus. 

 The great majority of the fibres leave the chain by the 

 sacral grey rami to the sacral nerves, and reach their destina- 

 tion by the dorsal nerves of the penis or clitoris, the genito- 

 anal and the scrotal nerves. A^ certain number of this set- 

 but relatively few— run by the hypogastric nerves. The 

 viscero-inhibitory fibres in the sacral nerves all pass into the 

 pelvic visceral branches of those nerves. The fibres to the 

 striated erector muscles run direct through the perineal 

 nerve, genito-anal nerves and the nervus dorsalis. 



The upper set of fibres have nerve cells upon them 

 which for those which travel by the sacral grey rami are 

 placed in the sacral ganglia, for those which travel by the 

 hypogastric are placed in the hypogastrics or a little nearer 

 their peripheral ends. 



Of the lower set of fibres those which run to striated 

 muscles resemble ordinary motor nerves, and have no nerve 



^Jotirii. of Physiol., vol. xiii., p. 683, 1892. 

 "^ Ibid., p. 675, 1892. 



