The ffoii Ores of_ the Mesabi Range. — Spuii'. 335 
teriorly by the rapid growth of the body whorl and the ex- 
pansion of its dorsal margin. Surface very faintly marked 
by concentric lines. External trace of the suture on lower 
three-fourths of shell exceedingly faint. Dimensions: height, 
5 mm.'; diameter of aperture, (H mm.; height of external spi 
ral, 1.2 mm. This is the type of the genus. 
Naples beds; Whetstone gully, near Honeoye lake, X. Y. 
(Named for Mr. W. B. Marshall, of Albany, conchologist of 
the New York State Museum.) 
THE IRON ORES OF THE MESABI RANGE.* 
By J. E. Sri'RR, Gloucester, Mass. 
(plate viii.) 
Preliminary Note. 
The information on which this paper is based was gathered 
by the writer while in the employ of the Geological Survey of 
Minnesota. Only an outline of some of the more important 
results of this study is given here; the full account is con- 
tained in Bulletin X of the survey. 
Limits of the Mesabi Range. 
The Mesabi range in Minnesota may be for convenience 
separated into three geographical divisions, characterized by 
sufficient geographical differences: The Western Mesabi, 
which extends from the Mississippi river to the Embarras 
lakes, on the eastern edge of range Lfi \Y. ; the Eastern 
Mesabi, reaching from the Embarras lakes to the region of 
Gunflirrt lake ; and the International Boundary division, which 
stretches from Gunnint lake east to Pigeon point. In the 
Western Mesabi region lie all the mines at present worked, 
and it is to this section alone that the observations made in 
this paper are intended to be strictly applicable. The chief 
ore-bearing district lies between the Mesabi Chief mine on the 
west and the Hale on the east, a distance <>f about forty 
miles. 
♦Published by permission of tin* State Geologisl of Minnesotji 
