Boas] GEOMETRIC FORMS 309 
The zigzag.—As has previously been intimated, there are two dis- 
tinct forms of zigzags, that composed of diagonal lines, arranged in 
horizontal or vertical series, and that composed of horizontal and 
vertical lines necessarily arranged diagonally. Of these the former 
are by far the most numerous. Horizontally arranged, especially 
when combined in some way with triangles, a single-line zigzag 
is most frequently called a necklace (sketch 77, pl. 79). Double or 
triple lines of this character are called snake, snake track, mountain 
tops, zigzag, caterpillar, or rarely the pack-strap design, since some 
form of this zigzag was usually taken for the decoration of the pack- 
strap. Sketches 79 and 80 show these figures. When double zigzags 
are arranged so that the imner points touch and the space between the 
lines is a series of diamonds they are regarded as more typical pack- 
strap designs, and are then described as having connected points or 
open middles. In addition to the usual interpretations of snake 
track, ete., such lines, particularly if there are many of them, are 
interpreted as ‘‘rainbow connected” and necklace (sketches 81 and 
82). The wide zigzag line (sketches 83 and 84), having a subdivided 
surface is usually called a snake design, occasionally necklace. A 
number of variants of this type of zigzag (85 to 88), in which some 
or all of the points are truncated, are given the following names: 
zigzag with flat points, half circles connected, going back and forth 
in half circles, mountain, cloud, rainbow, deer-fence, and embroidery. 
Only rarely are they termed snake tracks or part of a gravebox 
pattern. The exact name chosen for these figures on any particular 
occasion depends largely on the nature and disposition of accompany- 
