1920.] NATURAL SCIENCES OF PHILADELPHIA 213 



Plate VII. — Artifacts of hematite and limonite. 

 Figs. 1, 2, 8.— Hones. 



Figs. 3, 11. — Lower aspect of planoconvex hones. 

 Figs. 3, 4, 5, 6, 7, 9. — Sinew dressers and hones combined. 

 Fig. 10. — Tool sharpener and dresser. 



Plate VIII. — Iron ore objects and homologues of gritty stone. 

 Figs. 1, 5. — Hones of iron ore. 



Fig. 2. — Iron-ore hone and sinew-dresser combined. 

 Figs. 2, 4. — Sinew dressers of iron-ore. 

 Fig. 9. — Sinew-dresser of sandstone. 

 Figs. 6, 7, 8. — Hones of quartzite and sandstone. 



Plate IX. — Irregular artifacts of hematite and limonite. 

 Figs. 1, 2, 3. — Stages of making hematite cones. 

 Fig. 4. — Concave rubbing stone, shaft-dresser. 

 Figs. 5, 8. — Tool sharpeners. 

 Fig. 6. — Heart-shaped artefact. 

 Figs. 7, 10. — Pyramidal rubbing stones. 

 Fig. 9. — Rubbing-stone socketed for thumb. 



