MR WM. TURNER ON VARIABILITY IN HUMAN STRUCTURE. 181 



After a course of about two inches it became muscular, and then ran parallel to 

 the first lumbricalis, and was inserted along with it. 



The flexor muscles of the toes, the arrangements of which I have more especi- 

 ally studied, were the flexor brevis digitorum, the flexor communis digitorum, the 

 flexor longus hallucis, the flexor accessorius, and the lumbricales, — an important 

 group of muscles, the different members of which are more or less intimately 

 related to each other in the sole of the foot. In order to form as precise a con- 

 ception as possible of their mode of arrangement in the foot I carefully dissected 

 fifty specimens, taking them without selection from the subjects which came in 

 my way in the ordinary course of my anatomical work, so that the variations 

 described must not be regarded as unusual or abnormal forms. The results I 

 have arrived at differ in many respects from the descriptions of these muscles 

 usually given in treatises on anatomy. Of these fifty specimens no two were 

 exactly alike, so that it would be necessary, in order properly to bring out the 

 extent of individual variation which they presented, that each should have a 

 separate description ; but as this would be tedious both to writer and reader, it 

 may suffice if I adopt some method of arrangement which may exhibit their most 

 important variations. 



In all the specimens the tendon of the flexor longus hallucis gave off, in the 

 sole of the foot, a slip or band which connected that tendon either to one or more 

 of the subdivisions of the flexor communis digitorum, or in part to that tendon, 

 and in part to the flexor accessorius. In its size this connecting slip varied 

 somewhat, and though at times flattened and membrane-like, yet was mostly in 

 the form of a rounded band. In every specimen it took a more or less important 

 part in the formation of the deep flexor tendons for one or more of the four outer 

 toes. In eleven specimens it ended solely in the deep flexor tendon for the second 

 toe ; in twenty specimens it bifurcated and ended in the deep flexor tendons for 

 the second and third toes ; in eighteen specimens it trifurcated, and ended in 

 the deep flexor tendons for the second, third, and fourth toes ; in one specimen it 

 divided into four parts, and ended in the deep flexor tendons for the four outer toes. 



Of the eleven specimens in which the connecting band went solely to the 

 second toe, it formed about one-half the deep flexor tendon for that toe in four 

 cases (fig. 9), the remaining half being formed partly by the flexor communis and 

 partly by the flexor accessorius. A much larger proportion than one-half in six 

 cases (fig. 11) ; and in one case it and the flexor accessorius together formed the 

 whole of the deep flexor tendon for the second toe, in the construction of which 

 the flexor communis did not consequently enter (fig. 3). 



Of the twenty specimens in which the connecting slip went to the second and 

 third toes, it contributed a larger share to the second than the third toes in 

 twelve specimens, in one of which it formed, with the addition of a few fibres 



