20 PRIMITIVE ART 
The decorative forms applied by the Indians may, on the 
whole, be described as a variety of combinations of the acute tent 
triangle and of the obtuse hill triangle with rectangles and straight 
lines. Circles divided into sections occur also quite frequently. 
All these forms are executed in a variety of color, which is gener- 
ally included in the symbolic interpretation of the design. 
The detailed arrangement of the decorative motives shows 
some characteristic differences among different tribes. Thus, we 
find that the Arapaho (Case 20 /) like to arrange their patterns on 
hide bags in a number of parallel stripes, and that in the painted 
designs they put on the color in rather small areas. The Sho- 
shone (Case 26 e), on the other hand, like to arrange the decora- 
tive field in such a way as to lay out a wide border which cuts out 
a central field. The designs in these areas are laid on in strongly 
contrasting colors, without leaving any white background to 
speak of. Similar differences may be observed in the bead-work 
of different tribes. Some — for instance, the Comanche (Case 26 
d) — prefer to arrange their patterns in delicate narrow bands; 
while others, like the Sioux, utilize large beaded surfaces. These 
may be observed on moccasins, bags and pouches, on which 
white or colored beads form the background, from which the de- 
signs are set off. It seems, however, that some beaded and 
painted designs are common to all the tribes of the Great Plains. 
