CHURCn ON THE MYOLOGY OF TUE OK.OTG UTANG. 93 



tlie ligament which stretched across the plantar space Avas not so 

 strong as in the Orang, and thinned ont at its lower edge into a thin 

 fascia. Arising from this ligament, in the Magot and Cehis, were 

 three muscular slips, which were inserted by short and flattened 

 tendons into the tibial side of the first phalanx of the foiu'th and fifth 

 digits, and into the fibular side of the same bone in the second digit ; 

 thus exactly paralleling the arrangement found in the hand of these 

 monkeys. 



The Transversal is Pedis did not exist in any of the three monkeys. 

 It is mentioned by Duvernoy as being represented by ligament in 

 the Orang. It has been noticed to be wanting in man.* 



The Plantar Interossei presented a wide difterence from those in 

 the human subject. The first digit has one on the fibular side ; the 

 third and fourth digits, one on each side ; and the fifth digit, one on 

 the tibial side. They are large muscles, and not only occupy the 

 space between the bones, but also lie beneath them, covering them 

 in on the plantar surface ; each muscle is inserted into the upper 

 part of the bone of the first phalanx of its respective digit. 



In the Magot, the Interossei differ from the Orang, none of them 

 having any dorsal origin ; they therefore appear all to belong to the 

 plantar group. They are eight in number, and arise from the sheath 

 of the PeroncBUs Lonc/us. The fifth digit has one, the rest two. The 

 muscles are inserted into the sesamoid bones and head of the first 

 phalanx of the digits. The middle digit has a third, which, perhaps, 

 ought to be regarded as coming from the under part of the fascia, 

 sending the muscular slips before described to the second, fourth and 

 fiftli digits, rather than from the sheath of the Peronceus. Its in- 

 sertion is also different from the others, being inserted into the upper 

 and outer side of the first phalanx of the third digit. The second, 

 fourth and sixth interossei are the largest, and are visible on the 

 dorsal surface between the metatarsal bones. 



If now we briefly review the chief points of difference between the 

 muscular systems of the Quadrumana and of Man, we find in the muscles 

 of the trunk few points of interest. The abdominal muscles are much 

 thicker and stronger, to support the weight of the intestines when 

 the animal is on all fours. The cervical muscles also are stronger ; 

 but, with the exception of the digastric, differ very little from man's. 

 The digastric presents an intermediate condition in the Orang, the 

 chief insertion being into the angle and inner surface of the jaw, 

 corresponding to the usual insertion in the Quadrumana and lower 

 animals ; but it sends forwards a slender tendon lying on the inferior 

 surface of the mycohyoid muscle to be inserted, as in man, at the 

 symphysis of the jaw. The presence of the Clavio-troclielien appears 

 to be almost equalled in man by the division of the Levator Anguli 

 Scapulcs into several distinct portions, and their occasional insertion 

 into the spine instead of the angle of the scapula. 



• Mr. M'Whinnie, on the authority' of Bochmer. 



