136 TDE MAKQUETTE IKON-BEARING DISTRICT. 



regarded as Cambrian). This com])reliends conglomerates, breccias, con- 

 glomeratic schists, quartzites, dolomite, argillite, graywacke and graywacke- 

 schist, granite, felsite (?), diabase, diorite, peridotite, jjorodite, serpentine, 

 and raelaphyr or ])icrite. 



Wadswortu, M. E. Subdivisious of the Azoic Arclittan in Northern Michigan. 

 Science, December 23, 1802, page 355. 



In this article the author further subdivides the "Azoic," adding two 

 new formations to those recognized in the preceding paper. The table he 

 publishes shows the supposed equivalency between his own formations and 

 those proposed by Van Hise. 



SlICHIQ^VN GEOLOGICAL SURVEY. 



MTED STATES GEOLOGICAL SrRVEY. 



Azoic or Archean system : i 



Laureutian (?) period i Cascade formation... 



,, ■ ■ , f Republic formation . . 



Hnronian period 



I Mesnard formation . . 



Holyoke formation . . 

 egaiinee formation . 



Michigan period. 





Fundamental Complex. 

 Lower Marquette series. 



lUpper Marquette series. 



Gresley, W. S. a hitherto undescribed phenomenon in htematlte. Am. 

 Geologist, Yol. IX, 1S92, pages 219-223. 



Gresley describes a specimen of fibrous red hematite from the Lake 

 Supeinor region that seems to consist of fragments of botr3'oidal masses. 

 In the mid.st of tlie masses are cavities, around .jvhich the fibers sometimes 

 curve. No theory is proposed to account for these. It is suggested, how- 

 ever, that hematite, in "growing," encountered obstructions that have since 

 been removed. 



1S93. 



Wadsworth, jM. E. Report of the State Geologist for 1891-92. State Board 

 of Geol. Surv. for the years 1891 and 1892, Lansing, 1893, pages Gl-73. Signed 

 October 17, 1892. 



In this paper the author gives an account of the work done under his 

 direction by the IMichigan survey during the years 1891 and 1892. The 

 discovery of the conglomeratic base of the Republic formation, resting 



