MYOLOGY 145 



ficial layer in quadrupeds, it appears to us necessary to 

 recall the anatomical characters of the muscle as found in 

 man. The rhomboid arises from the inferior portion of the 

 posterior cervical ligament, from the spinous process of the 

 seventh cervical vertebrae and the four or five upper dorsal ; 

 thence passing obliquely downwards and outwards, it is in- 

 serted into the spinal border of the scapula, into the portion 

 of this border which is situated below the spine ; it some- 

 times extends to the middle of the interval which separates 

 this latter from the superior internal angle of the same 

 bone. 



The portion of the muscle which arises from the cervical 

 ligament and the seventh cervical vertebra is often separated 

 from the lower portion by a cellular interspace. For this 

 cause some anatomists have described the rhomboid as 

 consisting of two parts — the superior or small rhomboid 

 and the inferior or large rhomboid, on account of the position 

 occupied by each, and of their difference in volume. 



This muscle can only be seen in the region of the back, in 

 the space limited externally by the spinal border of the 

 scapula, below by the latissimus dorsi, and internally by the 

 trapezius, which covers it in the rest of its extent. It is 

 not in this space that it is seen in certain quadrupeds. As 

 we pointed out in the section on osteology, the spinal border 

 of the scapula is short, and it seems to be due to this 

 limitation in length that the trapezius and the latissimus dorsi 

 muscle are, at this level, in contact the one with the other 

 in such a way that they fill up the interval in which the 

 rhomboid is seen in man. 



In the horse we can partly see it in the superficial muscular 

 layer, but in the region of the neck only, at the superior 

 border of the shoulder. Indeed, as we have already pointed 

 out, the trapezius does not reach the occipital protuberance ; 

 for this reason a part of the anterior portion of the rhomboid 

 may be seen — that is, the portion which corresponds to the 

 superior part of the human muscle. 



But whether it be covered by the trapezius, or, as we 

 find in the cat and dog, by the masioido-hnmeral muscle 

 (see p. 150), which is very broad in this region, we do not the 



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