THUMB-FINGERNESS 



37 



The chart is thus complete as regards numbers 

 for the last five generations. 



The deformity which this family manifests aSects 

 chiefly the fingers and toes, but before describing it 

 in detail, it will be well to get a clear idea of the normal 

 anatomy of these parts. 



Fig. 1. 



Fig. 2. 



Fig. 3. 



Each finger and toe (except the thumb and big 

 toe) contains three bones, those of a finger being 

 longer than those of a toe, but otherwise similar. 

 Fig. 1 shows the three bones of a normal middle finger. 



