PRIMROSE ; THE ANATOMY OF THE ORANG OUTANG 
23 
ape we had definite proof that the two muscles belong to one another 
and form one single great muscle going from the ribs in the chest and 
from the cervical vertebrae in the neck to be inserted into the whole 
length of the vertebral border of the scapula. Bischoff states that in 
Macacus and other lower apes, this continuity of the two muscles is even 
more complete than in anthropoids ; in these a bundle arises from the 
first rib, which unites immediately with that arising from the seventh 
cervical vertebra, whilst in anthropoids a space exists between the two 
portions as a rule. One must remember, however, that the extensive 
origin described from the cervical vertebrae does not always exist in the 
Orang, as in my specimen there were only three slips of origin from the 
three upper cervical vertebrae. Hepburn^ describes four slips in the 
Orang dissected by him. In man there occasionally occurs partial union 
between the two muscles in question (Quain), whilst the origin of the 
levator may be extensive, receiving aponeurotic fibres even from the first 
and second ribs (Testut). 
It would therefore appear that, as a rule, the two muscles are distinct 
in man ; they are continuous in the lower apes, and the higher (anthro- 
poid) apes occupy an intermediate position where there is a partial con- 
tinuity. 
The Omo-cervicalis (plate III, fig. I, m.o\ is an interesting muscle which 
Bischoff asserts is not found in man,^ at all events of similar character 
to that occurring in apes. It arose in my Orang from the anterior aspect 
of the arch of the atlas vertebra and from its transverse process ; it was 
inserted into the clavicle on its posterior aspect at the junction of the 
middle and outer thirds of the bone, the attachment to the clavicle being 
1.5 cm. wide. The muscle has been described in the anthropoid apes 
and in the lower apes by Huxley,^ whilst in the various anthropoids it 
has been found by Cuvier,^ Vrolik,® Owen,® Chapman,^ Macalister,® 
and others. Its attachment to the shoulder girdle varies in apes and 
1 Loc. cit., p. 153, 
2 Loc. cit., p, 207. 
3 Loc. cit., Vol. I, pp, 428, 4156, 528, 596, 647, and Vol. II, p. 40. 
4 Georges Cuvier, “Anatomic compar^e ; recueil de planches de myologie,” Paris, 1849. 
5 Loc. cit., p. 18. 
6 R. Owen. “ Myology of Simla Satyrus,’’ Proceedings of the Zoological Society of London, Part 
I. i 83 o- 3 i» P* 29. 
7 H. C. Chapman, “ On the Structure of the Orang-Outang,’’ Proceedings of the Academy of Natural 
Science of Philadelphia, 1880, p. 161. 
8 Alex. Macalister. “The Muscular Anatomy of the Gorilla,” Proceedings of the Royal Irish 
Academy, Sr. 2. Vol. I, 1870-74, p. 501. 
