1866.] Mr. J. Wood on Variations in Human Myology. 229 



the lower grade represented by the homogeneous food-yelk with a cortical 

 layer, and possessed of rhythmic contractility, passing into the higher 

 represented by the formative yelk of a granular structure, and possessed 

 of a fissile contractile property only. 



IX. "Variations in Human Myology observed during the Winter 

 Session of 1865-66 at King's College^ London.^' By John 

 Wood, F.R.C.S., Demonstrator of Anatomy. Communicated by 

 Dr. Sharpey. Eeceived May 3, 1866. 



In the present paper are given the results of observations, made with the 

 greatest possible accuracy and care, of the muscular anatomy of thirty-four 

 subjects, chiefly of the male sex, with an especial view to the study of the 

 combinations of these abnormalities, and the directions in which they 

 chiefly tend. To enable the reader more readily to comprehend these re- 

 sults, the author has tabulated them in the sheet appended to the paper. 

 In the Table the names of the muscles placed at the head of each column 

 refer to those in which more than one variety has been observed in the 

 session. They will be found to correspond very closely with those given 

 in the former papers by the author. In columns 4, 21, and 27 are placed 

 those of which only one example has been met with. Some of these, how- 

 ever, are of much importance. 



To explain the nature of the abnormality more precisely than could be 

 done in the Table, a word or two will be necessary on such of the specimens 

 as may be considered novel or typical. 



Four columns are occupied by variations of the head and neck, the ex- 

 amples of which amount in the aggregate to twenty-two ; some of the 

 muscles in these may, however, strictly be considered as muscles also of 

 the upper extremity, especially those in col. 3, which I have denominated 

 cleido-occipital. 



Col. 1 . Platysma myoides. — The first of the two varieties noted (in 

 subject 20) was connected with the inner side of the lower end of the nor- 

 mal muscle, the fibres passing in a broad band downwards and inwards, 

 over the origin of the sterno-cleido-mastoid, the clavicle, and upper fibres 

 of the pectoralis major to be inserted into the fascia covering the sternum 

 as far down as the third costal cartilage. 



The second (subject 29) was connected internally with the sternal fascia 

 between the second and third costal cartilages, and crossing obliquely out- 

 wards and downwards over the lower fibres of the pectoralis major and 

 axillary cavity, became attached to the tendon of the latissimus dorsi, ex- 

 actly as we find its homologue, the panniculus carnosus, to do in the lower 

 animals. This variety of the Platysma does not appear to have been pre- 

 viously recorded. 



2. Digastric. — The two varieties of this muscle were found, as usual, 

 in the anterior belly, which was double. In the first (No. 1) the redundant 

 belly was attached by the median raphe to the one on the other side, and 



