1887]  Lncised Boulders in the Upper Minnesota Valley. 639 
INCISED BOULDERS IN THE UPPER MINNE- 
SOTA VALLEY. 
BY T. H. LEWIS. 
HERE are other inscribed. rocks in the same region besides 
those of the Thunder Bird’s Track described in the AMER- 
- ICAN NATURALIST for May, 1886, which, like them, should be 
DIAGRAM N?! 
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8 
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i 3 : : fr kas 
| . ean PS ks eS 
Zz, 30 4a So Centimetres 
_ preserved jen oian The accompanying diagrams and k 
verbal descriptions will account for three. 
E SE ESE SE AENA D ee ee, 
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