518 Mr. J. Wood on Variations in Human Myology. [May 23, 



IV. " Variations in Human Myology observed during the Winter 

 Session of 1866-67 at King^s College, London/'' By John 

 Wood, F.R.C.S., Demonstrator of Anatomy (with a Table and 

 Seven Drawings). Communicated by Dr. Sharpey. Re- 

 ceived May 9, 1867. 



A largely increased number of abnormalities has been the result of 

 a systematic observation of tJiirty-six subjects during the past winter 

 session. This has been owing partly to the comprehension of one or 

 two irregularities which are commonly referred to in systematic works 

 on anatomy, — such as the coronoid origin of the flexor pollicis longus and 

 the insertion of the extensor ossis metacm^pi pollicis, partly to the more 

 productive results of a vigilant superintendence, an increased efficiency 

 in the dissections. Por much of this the author's thanks are due to the 

 able help of his assistants, Messrs. Perrin and Amsden, and the intelli- 

 gent zeal of many of the anatomical class. Mainly, no doubt, the 

 increase is owing to an absolutely larger number of abnormalities. The 

 value of the observations to the author is, of course, much increased by 

 his having personally and thoroughly examined every specimen before 

 noting it down, and, if possessing sufficient interest or novelty, sketch- 

 ing it from the subject. The exact numerical results thus arrived at 

 have, in almost all important particulars, confirmed, but in some modi- 

 fied, the conclusions as to frequency and coincidence given in the 

 author's former papers. What the author has termed the lines of 

 variation, i. e. the particular muscles which are by far most commonly 

 affected, are nearly identical with those of last year, as will be found by 

 comparing the columns of the appended Table with those of the former. 

 Only a few diff*erent wiU be found in the columns occupied by the 

 sundry specimens. 



Out of the total number of 295 abnormalities of muscles in 34 sub- 

 jects showing abnormalities (as compared with 132 in 32 subjects of 

 last year), we have in the head and neclc 11 muscles affected with va- 

 rieties, as compared with 10 of last year. In the arm we have 30 lines 

 of muscular variation as compared with 26 ; while in the leg we have 20 

 as compared with 14 in Jast year's subjects. 



The increase wiU. be seen to be disproportionately greater in the leg. 

 In this part also is the absolute number of the specimens increased ; for 

 while those in the head and neck proper (acting only on the parts or 

 bones of the head, neck, and spine) are 15 as compared with 10, and 

 those of the arm 157 as compared with 83, those of the leg are increased 

 to 106 as compared with 39. This raises the proportion of abnorma- 

 lities in the leg to two-thirds of those in the arms, as compared with 

 rather less than one-half found last year. This seems to have some 

 significance in being coincident with an increase in the number of female 

 subjects to 12, as compared with 4 in last year's list. The author has 



