MASTODON REMAINS FOUND IN GRATIOT COUNTY, MICHIGAN. 



H. M. MACCURDY. 



The relation of the remains of Mastodon to the glacial and post-glacial 

 deposits has always been of interest, and information concerning this relation 

 is of value in the study of the distribution of these animals both geographically 

 and chronologically. 



Parts of three skeletons of Mastodon have been found in the vicinity of 

 Alma. The parts as they were found are now in the Hood Museum of Natural 

 History at Alma College. 



The Alma Area,* which includes the north half of Gratiot County, presents 

 three distinct physiographic types of surface : old lake deposits, low morainal 

 hills, with intermorainal deposits, and fossil beaches. The fossil beaches divide 

 the area roughly into two nearly equal parts ; passing in the main in a north 

 and south direction across the area somewhat east of Ithaca, which is in the 

 geographic center of the county, and St. Louis, lying near Alma on the north- 

 east. To the east of this line are found the old lake deposits, now fertile farm 

 lands ; to the west are found low morainal hills with inter-morainal depres- 

 sions, with occasional outwash plains. The morainal hills increase in elevation 

 toward the west, but they are very well suited to and are occupied in farming. 

 The old lake beaches are obliterated in many places, but are rather clearly 

 marked in others. This beach is the highest in the series of beaches surround- 

 ing the present Saginaw valley and bay, and would thus be the beach of the 

 old Lake Saginaw. 



The fragments of the first skeleton in the collection were found on the 

 farm of the late Mr. William Pitt on the south half of the northwest quarter 

 of Section 22, Township 12, Range 4, west. They were lying in the surface 

 layers of the gravelly out wash and were not in contact with muck. The frag- 

 ments were scattered and were apparently disturbed by water. They show 

 considerable mineralization and are well preserved, though much broken. 

 From this specimen there were several teeth, the atlas, a portion of a humerus, 

 one-half of the lower jaw, a few vertebrae and ribs, and pieces of other bones. 

 The degree of mineralization and the position in the deposits indicate a period 

 considerably earlier than in the cases of the other two siJecimens to be men- 

 tioned. 



The parts of the second specimen to be found were found in what is now 

 the southern part of the City of Alma, near the Alma plant of the Michigan 

 Sugar Company. Tliey were imbedded in muck, which had caused considerable 



'Soil Survey of the Alma Area, Michigan. Hearn, W. Edward, and Griffin, A. M. ; 

 U. S. Dept. of Agri., Bureau of Soils, Advanced sheets, Field Operations, 19 104. 

 21st Mich. Acad. Sci. Kept., 1919. 



