402 



II\KRI> II. WILDER. 



lower one may appear as a loop, either facing in (Fig. 17) or out 

 (Figs. 18, and 19). Finally the two parts may both become 

 entirely effaced (Fig. 20) the last sign of the former pattern being 

 the degeneration triradius, with the separation of the area of 

 otherwise parallel lines into the two parts of an original S-shaped 

 pattern. 



FIG. 19. 



A double S-shaped pattern, in which the upper loop has disappeared, 

 and is represented by lines that show no trace of a curve. 



FIG. 20. This shows the ridges covering a hypothenar region, covered by 

 parallel cross-lines, but showing a degeneration triradius, dividing the entire area 

 into halves. It may be supposed that during the evolution of this form it may be 

 evolved from an S-shaped spiral pattern, which has developed a degeneration 

 triradius, and that each pattern of this has degenerated completely. 



It is possible to bring into the category of spread-out S-patterns 

 certain cases that consist simply of a rather small and narrow 

 loop, placed very low down on the palm, adjacent to the carpal 

 margin (Fig. 21). This loop suggests the lower half of the double 



