IN PATAGONIA AND FUEGIA 127 
lance-head of translucent, opalescent agate (Fig. 9, no. 5) is 
very skilfully flaked all over both surfaces. This blade is very 
thin (about 4 mm. at the thickest part) and the surfaces are 
almost flat. The base is notched to form a tang and pair of 
barbs. (2) Arrow- and lance-heads made from a black or 
dark grey chert, usually rather coarsely flaked all over, and 
frequently of imperfect symmetry (Fig. 9, nos. 6-10). Nearly 
all have very broad tangs, usually concave at the base. Barbs 
are only slightly indicated. More rarely the base of the blade 
is without a tang and is notched or concave, as in Fig. 11, 
no. 1, which shows a very thin blade, flaked with considerable 
skill over both surfaces. Unfortunately the point has been 
broken away. The apex of the blades of this group varies 
greatly in shape. In some the sides are straight and converge 
to form a point, more or less obtuse (Fig. 9, nos. 6, 7; 
Fig. 11, no. 1). In others the sides are curved and the apex 
is either blunt-pointed or forms a continuous curve with the 
sides, resulting in a wide, convex cutting edge which may be 
semicircular (Fig. 9, nos. 8, 9, 10). This latter type puzzled 
Spencer as to their use (see his letter to me). Possibly they 
were knife-blades, rather than arrow-heads, but their hafting 
tangs are similar to those of the pointed examples, and all 
gradations from definitely pointed to semicircular-edged 
types occur, making it difficult to separate the two groups 
on a basis of apparently different functions. They cannot be 
classed as ‘scrapers’, though tanged, bevel-edged scrapers of 
identical outline are well known, since the edge is not 
bevelled, both surfaces being equally flaked to produce the 
cutting-edge. If they served as arrow- or lance-heads their 
function must have been to cause haemorrhage without deep 
penetration. Most of the examples in this second group 
appear to have been collected around San Julian and Santa 
Cruz. 
A very few borers are included in the collection, of which 
