REPORT ON THE SEALS. 197 



from the plantar surface before the peroneal groove of the cuboid to the base of the metatarsal 

 of the 5th digit, and finally enters the groove on the plantar surface of the cuneiform bones. It is 

 inserted into the base of the proximal extremity, on the plantar and dorsal side of the metatarsal of 

 the hallux, the ligaments of the foot forming a channel for it by bridging over the grooves. The 

 high origin of this muscle from the femur will give support to the knee, and make up for the 

 absence of the external lateral ligament. 



In Arctocephalus gazella it is situated on the outer side of the leg, and arises from the external con- 

 dyle of the femur, out of the same tendon which gives origin to the popliteus and plantaris muscles ; 

 and from the tibia and fibula at the tibio-fibular ankylosis, as in Phoca. It courses backwards 

 between the extensor communis digitorum and the dorsal malleolus, turns outwards over the inner 

 border of the fibula and gains the dorsal surface, enters the outer groove of this surface, runs over the 

 tendons of the peronei brevis and quinti digiti, traverses the inner groove on the dorsal surface of 

 the os calcis, and turns down into the groove of the cuboid bone, descending obliquely forwards over 

 the cuneiform bones to the proximal extremities of the metatarsals. It is inserted into the dorsal 

 proximal extremity of the 1st metatarsal bone. In Otaria and Trichechus it has origin from the 

 femur, and is inserted into the head of the 1st metatarsal, and joins the fascia to that of the 4th. 

 In the Phocinse it extends the ankle and turns the dorsal border of the foot outwards ; in 

 Arctoc&phalus only it will raise the heel in walking. Humphry and Lucae describe no tibial fibres. 

 In the Phocinae it is supplied by the musculo-cutaneous nerve. 



The Peroneus quinti digiti in the Phocixue and Macrorhinus is a flat band-like muscle which 

 arises from the outer surface of the peroneus brevis, upon which it is planted, and from the outer 

 surface of the head of the fibula, dorsal to the peroneus longus. It passes backwards to the 

 posterior end of the fibula, and is closely adherent to the peroneus brevis, from which it is with 

 difficulty separated. About the lower third of the outer side of the fibula it forms a small tendon, 

 which passes through the annular ligament behind the malleolus in front of the tendon of the 

 peroneus brevis. It goes in this order over the inferior groove of the os calcis, and is inserted into 

 the outer and dorsal surfaces of the distal end of the 5th metatarsal, and the proximal end of the 

 1st phalanx of the 5th digit. 



In Arctocephalus gazella it lies on the peroneus brevis, and arises from the head of the fibula 

 below the soleus, and from the anterior quarter of the dorsal surface of the fibula. It is adherent to 

 the peroneus brevis, passes backwards in the inner groove on the dorsal surface of the fibula upon 

 the tendon of the brevis, then it enters the groove of the os calcis which is on its outer surface, 

 and proceeds backwards upon the dorsal side of the 5th metatarsal bone to be inserted into the 

 proximal dorsal extremity of the 1st phalanx of the 5th digit, expanding before reaching it. In 

 the Phocinse it is supplied by the external popliteal nerve. 



The Peroneus brevis, the peroneus secundus of Lucae, in the Phocinag and Macrorhinus 

 leoninus is the largest of the group, and arises from the outer surface of the head of the 

 fibula ; and from the anterior three-quarters of the outer surface of this bone, the fibres arising 

 from the anterior half being dorsal to the outer border, and the remaining fourth of the muscle 

 dorsal to the ventral border. Near the malleolus it forms a strong tendon, which goes with the 

 peroneus quinti digiti but to its upper side through the annular ligament, and in this order enters 

 the inferior groove on the os calcis, and is inserted into the dorsal surface and distal end of the 5th 

 metatarsal. 



