94 EXPLORATION OF BURTON MOUND [BTH. ANN. 44 
fracture 22 mm. long. There are scratches running in several directions on the 
surface of the concavity. 
Ironstone concretion, 32 mm. diameter, 11 mm. high; concavity 7.5 mm. 
deep. The rim is squared. The inside of the concavity shows scratches from 
former use. (PI. 16, g.) 
Ironstone concretion cup, 28 mm. diameter, 19 mm. high, coneavity 15 mm. 
deep. Rim neatly squared. 
Ironstone concretion cup, 22 mm. diameter, 10 mm. high, concavity 7 mm. 
deep. 
Ironstone concretion cup, 82 mm. diameter, 28 mm. high, 13.5 mm. deep. 
Shaped and sized like a deep-cupped rock oyster shell. Rim. rounded and un- 
even. 
ARROWHEADS, SPEARHEADS, DRILLS, AND KNIFE BLADES 
A large number of flint points of this description were taken, many 
of them in a fragmentary condition. These instruments can be 
classified according to (1) use, (2) shape, (3) material. All three 
of these classifications are difficult. We also took quantities of flakes 
or fragments of the same materials as those used in the manufacture 
of the chipped implements. 
As regards use, it is clear that the great majority of the objects are 
arrowheads. Those too large or heavy to be arrowheads may have 
been spearheads or may have been used mounted or unmounted for 
several other purposes. A class of points triangular in section may 
have been drills, but may also have been used on arrows. Only when 
showing traces of handles or of the tarring for handles can blades, 
although of the right shape and size, be accepted as knife blades. 
The knives do not necessarily have both edges sharp. (Cp. Wilson,'* 
1eiG Sil.) 
The most elaborate classification of arrowheads according to shape 
is that offered by Wilson.'* This classification we reproduce here, 
suggesting in brackets certain abbreviations by the use of which 
the shape of arrowheads can be expressed with some degree of 
satisfaction. 
I, Lear SHaArep [L] 
This division includes all kinds: elliptical, oval, oblong or lanceo- 
late forms bearing any relation to the shape of a leaf, and without 
stem, shoulder or barb. 
pointed at both ends [ambipointed, a]. 
General shape_-} oval [o]. 
hong and narrow, parallel edges [slender, sl]. 
convex [ex]. 
Base see sees straight [truncate, st]. 
coneave [cv]. 
14Thomas Wilson, Arrowheads, Spearheads, and Knives of Prehistoric Times, Annual 
Report of United States National Museum for 1897, Washington, 1899, pp. 811-988; 
classification, pp. 887-946, especially pp. 890-891. 
