1868.] Mr. J. Wood on Variations in Human Myology. 485 



by Murie in his dissection of a Bushwoman (Journal of Anatomy and 

 Physiology, No. 2, May 1867, p. 198). 



2. Sterno-cleido-mastoid. — In 4 male and 3 female subjects out of the 

 36, the clavicular origin of this muscle was double, or divided into two 

 portions. In all but one of these the cleido-occipital was also present. 



3. Omohyoid. — In 2 male and 2 female subjects the posterior belly 

 presented an additional or clavicular origin. Three were found on the 

 left side only, and one on the right only. On the opposite side of one 

 male (No. 15), a muscular slip arising from the middle of the clavicle 

 (quasi-clavicular origin of the omohyoid) passed upwards and inwards to 

 join the sterno-thyroid at its insertion, the omohyoid itself on that side 

 being normal, with the exception of having no median tendon. In No. 9 

 the omohyoid, otherwise normal, passed through an opening between the 

 normal origin of the sterno-thyroid and an abnormal slip to that muscle 

 from the clavicle, at the junction of its middle and outer thirds. In No. 13 

 also, the median tendon of the omohyoid was wanting, a continuity of 

 muscular fibre passing from its origin to its insertion. This is always the 

 case in Monkeys and the lower mammalia. In a male subject (No. 2) the 

 anterior belly was double, the superior one fusing with the hyoglossus and 

 middle constrictor muscles, and receiving, moreover, a slip from the middle 

 of the sterno-thyroid (see fig. 2 A). 



Out of 70 subjects now examined by the author with a view to the abnor- 

 malities of the omohyoid muscle, viz. 40 males and 30 females, the anterior 

 belly has been found double in 4 males, in two on both sides, and in two on the 

 right side only. In one male it was triple on both sides. A clavicular origin 

 of the posterior belly has been found in 2 males on the left side only ; and in 

 3 females, of which 1 was on both sides, 1 on the right, and 1 on the left side 

 only. The median tendon has been found absent in 2 males, in 1 on the right, 

 and in the other on the left side only. Thus in 12 out of 70 subjects some 

 irregularity existed in this muscle — a proportion greater than that found 

 by Professor Turner in 373 subjects, viz. 5 or 6 per cent. (Irregularities 

 of the Omohyoid, p. 2). A clavicular origin of the posterior belly was 

 found in .5 subjects out of the 70, or about 7 per cent. Turner found it 

 in 17 out of 373 subjects, i. e. rather more than 4 per cent. In 5 out of 

 70 subjects (also about 7 per cent.) the anterior belly was found double or 

 triple. Turner does not mention this abnormality, but found the anterior 

 belly blended with the sterno-hyoid in 4 out of the 3/3 cases. 



4. Digastric. — In 3 subjects, 2 male (Nos. 13 & 16) and 1 female 

 (No. 34), the anterior belly of this muscle was double, in the males on 

 both sides, and in the female on the left side only. In No. 13 the super- 

 numerary head decussated across the median line with its opposite fellow. 

 This variety has been before recorded by Fleischmann (Anat. Wahrnehm. 

 in Erlang. Abhand. Bd. i. S. 26 & 27, Taf. i. fig. i. 1810), and subsequently 

 by Gantzer (Dissert. Anat. Muse, varietatis sistens. 1813), Soemmerring, 

 Theile, and Henle. 



2 T 2 



