+ 
MUSCLES OF THE SHOULDER AND ARM. 31 
pass to the spine of the scapula, and are inserted along 
the greater portion of itsanterior edge. There is usually 
a space between this and the anterior division near the 
origin of the fibres, which is filled up with fat, connec- 
tive tissue, lymphatic glands, etc. 
c. THE PosTERIoR TRAPEZIUS arises above the spi- 
nous processes of the anterior thoracic vertebree in a 
continuous line with the middle trapezius. The fibres 
pass obliquely forward to be inserted along the pos- 
terior edge of the outer or vertebral portion of the 
spine of the scapula. 
In man these three divisions are more completely 
united to form a single trapezius muscle. 
Cut the three divisions of the trapezius at their wn- 
sertions and reflect the cut ends dorsally to thetr origins. 
Lhe following muscles will be exposed. 
2. The Rhomboideus Minor. It arises from the 
dorsal mid-line above the spinous processes of the 
posterior cervical vertebree, just beneath the origin of 
the trapezius. The fibres pass obliquely to the scapula 
and are inserted into the anterior angle of the vertebral 
margin. 
a. THE OcciPITo ScaPuLARis. Lying along the inner 
margin of the rhomboideus minor is a narrow band of 
muscle, the occipito scapularis, which arises from the 
occipital bone and is inserted into the scapula along 
with the rhomboideus, the two forming one muscle at 
the insertion. This muscle is known also as the rhom- 
boideus capitis or rhomboideus occipitalis in human 
anatomy. 
3. The Rhomboideus Major arises from the spi- 
nous processes of the four or five most anterior tho- 
racic vertebree—its origin being in a continuous line 
with that of ‘the rhomboideus minor, from which 
