Stage 3.5 Biface Preform Summary

This table totals Stage 3.5 biface preforms. This stage is intermediate between Callahan's (1979) Stage 3 and Stage 4.本表格统计了3.5阶段两面器坯料（biface preform）的总量。该阶段为卡拉汉（Callahan）1979年提出的第3阶段与第4阶段之间的中间过渡阶段。