90 
PROFESSOR WOOD ON THE NECK- AND SHOULDER-MUSCLES. 
the superior curved line of the occipital bone, as well as by a more or less marked 
areolar interval between the two. The fibres of the latter muscle are directed from the 
clavicle upwards and forwards in such a manner as to become, in the upper part of the 
neck, entirely covered by those of the sterno-mastoid, which form here the entire pos- 
terior border of the compound human sterno-cleido-mastoid muscle, to the exclusion 
of those of the cleido-mastoid, which pass more deeply and are directed more forwards 
to the mastoid process. 
We have found the cleido-occipital muscle more or less developed in 37 subjects out 
of 102, viz. in 27 out of 68 males, and in 10 out of 34 females. In 34 it was found on 
both sides, and in 3 on one side only. In two instances in which it was found on one 
side only, there existed on the opposite side a levator clavicular muscle, showing a sort 
of correlation between the two formations. In two instances the muscle was double, or 
divided into two distinct portions. In two more male subjects the formation was so 
peculiar as to merit a more detailed description ; one of them was the subject of fig. 29, 
Plate XI. Besides the ordinary clavicular attachment (c), which was connected with the 
bone near to that of the trapezius (T), so as almost entirely to cover the posterior triangle, 
there arose from the sternal end of the clavicle, external to and partially separate 
from the sternal origin of the sterno-mastoid , a strong flattish tendon giving origin to a 
considerable bundle of parallel muscular fibres ( c These crossing upward and back- 
ward, superficial to the origin of the cleido-mastoid proper ( b ), joined, about the middle 
of the neck, the fibres from the ordinary origin (c), and were inserted with and anterior 
to them into the superior curved line of the occipital bone. The appearance of a com- 
pletely double sterno-cleido-mastoid was thus given to the subject, bearing a striking 
resemblance to the formation of the homologous muscles in the striped Hyiena, Polecat, 
Genette, Coati, and Marmot, as figured in Cuvier and Laurillakd’s plates of these 
animals. 
The muscular variety which I have distinguished by the name of cleido-occipital has 
been observed and described by various writers as an occasional variety of the sterno- 
cleido-mastoid or trapezius muscles. 
It is mentioned by Sommerring (De Corp. Hum. Fabric, p. 112), and was found by 
Kelch coexistent with a double sterno-cleido-mastoid , the whole possibly having been 
a formation similar to that last described (Beitrage, xxi. p. 31). 
Meckel describes it, both in the human subject and in animals. In the latter he 
states that it sometimes joins, below, the anterior fibres of the deltoid ( cephalo-humeral ) ; 
and in his description of Ateles and Magot, and some other animals, he seems to have 
looked upon it as a variety of the acromio-trachelien ( levator clavicular ), and through 
this arrangement he appears, moreover, to have connected the latter with the trapezius 
rather than with the levator anguli scapulae , as indicated by Cuvier (Meckel, De Du- 
plicitate Monstrosa, pp. 40, 41, and Muskellehre, p. 475). 
Tiieile describes an oblique slip of muscle, three lines wide and one thick, attached 
to the superior curved line of the occipital bone, partly under the trapezius , and spreading 
