MAMMALIA. 



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ramify in the broad ligament with branches of this, in a similar manner to those in the 

 mesentery, to be distributed on the horn of the uterus ; the ganglion then sends down 

 the hypogastric plexus to join branches of the sacral nerves. In the porpoise, small 

 branches are sent from the semilunar ganglia to the aortic plexus, and this keeps 

 receiving fine branches from the prolongation and ganglia, which pass through a 

 tendinous fascia, and are therefore with much difficulty followed ; below the seventh 

 lumbar vertebra the filaments sent to the aortic plexus are extremely minute. The 

 aortic plexus sends filaments in the portion of mesentery corresponding with the 

 mesocolon towards the lower portion of the intestines ; it is then continued down to the 

 large ganglion of the hypogastric plexus, which sends off spermatic nerves in several 

 branches to pass with the reticular blood-vessels to the testes ; it sends one or two 

 orancb.es to ramify and communicate with filaments of the branch of the internal 

 judendal for supplying the bladder and rectum. In the female, there is a large 

 ganglion in the aortic plexus ; this gives branches to a ganglion which sends filaments 

 towards the ovary with the reticular blood-vessels ; the aortic plexus then terminates 

 in the large ganglion of the hypogastric, which divides for each side, and sends off 

 the uterine nerves, and also small branches to join those of the internal pudendal for 

 the bladder and vagina. The quantity of nerve proceeding from the internal pudendal 

 for the bladder and rectum, and for the vagina to be joined with that of the hypo- 

 gastric plexus, is very small ; it is however in proportion to the very diminutive 

 bladder and rectum, and must be considered to furnish these as mere receptacles and 

 passages. As there is very little distinction between the upper and lower portions of 

 the intestines, except that they become gradually smaller, so there is no perceptible 

 difference in their nerves ; and as there is no need for a capacious coecum and colon 

 for completing the assimilation of the food, a more simple state of the rectum suffices, 

 and diminutive nerves from the hypogastric and sacral are only required. 



In several male animals, the external spermatic nerve communicates with a branch 

 of a lumbar ganglion sent to the aortic plexus, and near this, but not at the precise 

 spot, the internal spermatic nerve arises. The hypogastric plexuses are generally very 

 similar to those in man, but more or less extensive, and combined with a different 



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