MAMMALIA. 



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In the pig the posterior tibial nerve having given branches to the muscles of the 

 leg, and sent the branch down at the back of the gastrocnemius muscle to the outer 

 side of the leg, gives filaments to the inner side of the heel, and near this part divides 

 into the inner and outer plantar 'nerves ; the inner is continued onwards and supplies 

 the small inner toe, and the first large toe, and the inner side of the second. The 

 outer plantar passes underneath the flexor tendons, and is continued onwards to divide 

 for the outer side of the second large toe, and the outer small toe ; it sends the deep 

 plantar into the sole to supply the short muscles situated there. The anterior tibial 

 nerve gives branches to the ligaments at the back of the foot, and sends a branch to 

 supply the first small toe and the inner side of the first large one ; the rest of it gives 

 branches to the small muscles on the back of the foot, and then passes forward to join 

 the branch of the peroneal given to the outer side of the first, and the inner side of the 

 second large toe ; the continuation of the peroneal, after emerging just above the instep, 

 supplies the outer side of the first large toe, both sides of the second, and the last 

 small one, the branch sent to the outer side of the first and the inner side of the second 

 large toe, receiving a branch of the anterior tibial. 



In the porpoise the distribution of dorsal nerves is similar to that in mammalia. 

 The external divisions of the anterior trunks of the dorsal nerves are extremely small, 

 being mere branches and not a division of the trunk as in man, but the whole continues 

 progressing forwards, and giving off small branches in its course to the intercostal 

 muscles, the abdominal muscles, and skin; the three upper ones supplying the 

 triangular muscle of the sternum. The posterior trunks supply the muscles and skin 

 at the posterior part of the spine. There are eleven that may be compared with the 

 lumbar and sacral, and from the lowest of these the anterior caudal trunk begins. 

 The remaining fourteen are entirely caudal. Each of nine of the upper lumbar and 

 sacral give off a considerable branch near the spine to the psoas muscle. The five 

 uppermost pass forwards, giving off filaments to the psoas muscle, and then reach the 

 muscles at the anterior part of the abdomen, and distribute filaments in their course. 

 Branches given off from the next six terminate in the psoas muscle, the lowest five 

 then form the internal pudendal nerve, but, like the rest, send forward a smaller branch 



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