160 MAMMALIA. 



between the ribs, and are distributed nearly as in the fox. There are six lumbar and 

 six sacral in one subject, and five lumbar and seven sacral in another, besides three or 

 four caudal, but it is not necessary to speak of these separately. The third lumbar 

 sends off a branch, which gives a branch to the great psoas muscle, and one to join the 

 fourth for the anterior crural nerve, it then becomes the external cutaneous nerve to 

 pass on the outer side of the thigh ; it sends off another large branch corresponding 

 with the external spermatic, which communicates with a large branch of the third 

 lumbar ganglion of the sympathetic, gives a branch to the small psoas muscle, and then 

 passes underneath the lower border of the abdominal muscles, to which it sends a 

 branch and becomes distributed on the mamma. The anterior crural nerve arises from 

 the third, fourth, fifth, and sixth lumbar nerves ; the obturator arises from the fourth, 

 fifth, and sixth ; the sciatic arises from the sixth lumbar and the two first sacral, it has 

 also a slight communication with the third ; the principal part of the third and fourth 

 sacral joined by a small branch from the portion of the sciatic arising from the second 

 form a junction, which gives off the internal pudendal to pass at the side of the arch of 

 the pubes and distribute filaments to the neck of the bladder, and terminate on the 

 clitoris,_ vagina and external parts, and the connecting muscle and membrane between 

 these and the mamma ; a branch of the external spermatic may be traced downwards, 

 and a branch of the internal pudendal upwards towards each other, but their com- 

 munication was not made out ; the rest of this junction communicates with another 

 nerve formed by part of the fourth and fifth, and sometimes part of the sixth, branches 

 are then given to muscles connected with the vagina, anus, and tail, and to the skin ; 

 another part of the junction of the fourth and fifth, with sometimes a branch from the 

 sixth, joins the hypogastric plexus, and sends branches along the inferior uterine artery 

 to the neck of the uterus and vagina, and is then distributed on the bladder, urethra, 

 vagina, and rectum. The remaining part of the fifth or sixth sacral forms the 

 beginning of the anterior caudal nerve, to which the anterior trunks of the remaining 

 spinal nerves below it become united ; the posterior trunks of these nerves form the 

 posterior caudal nerve, both of these are continued to the extremity of the tail, com- 

 municating by branches, and supplying one-half of each anterior or posterior surface. 



