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THE POPULAR SCIENCE MONTHLY 



Pig. 4. Petrified Wood. University of Mississippi. 



part of it is exogenous, good specimens of palm-wood are found in south 

 Mississippi. 



Most of the petrified wood in the state is found in the Lafayette for- 

 mation hut some is found lower down in the "Wilcox and other Tertiary 

 formations. Dr. Hilgard surmised that a great part, if not all, of the 

 silicified wood found in the upper formation was derived ultimately 

 from the several lignitic stages of the Tertiary. 



The petrified forest, or speaking more accurately, the group of silici- 

 fied logs, which I wish particularly to mention in this brief article, is 

 found. near Flora, seventeen or eighteen miles northwest of Jackson, the 

 state capital. Here is a large field where erosion is actively taking place 

 at the present time. Throughout the area are scattered logs and frag- 

 ments in varying stages of disintegration. 



An amphitheater some twenty or twenty-five feet deep and about one 

 hundred and fifty feet in diameter, where the Columbia loam and the 

 Lafayette sand have washed away down to the Tertiary formation, offers 

 the best single exhibit of the logs. At the mouth of the valley the ero- 



