Tlie Kezvecnaxuan m Minnesota. — Elftnian. 187 
H. Winchell. 13th Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 
1885, pp. 20-24. The crystalline rocks of Minnesota, N. H. Winchell. 
Ibid., pp. 36-38. 
17. Report of geological observations made in northeastern Minne- 
sota during the season of 1886, Alexander Winchell. 15th Ann. Rept. 
Geol. and Nat. Hist. Survey of Minn., 1887, pp. S-207. 
18. Geological report of N. H. Winchell. Ibid., pp. 209-399. 
19. Preliminary description of the peridotytes, gabbros, diabases and 
andesytes of Minnesota, M. E. Wadsworth. Bull. 2, Geol. and Nat. 
Hist. Survey of Minn., 1887, 159 pp., and 12 plates. 
20. Is there a Huronian group? R. D. Irving. Am. Jour. Sci., .3rd 
ser., vol. XXXIV, 1887, pp. 204-216, 249-263, 365-374. 
21. On the classification of the early Cambrian and pre-Cambrian 
formations. R. D. Irving. 7th Ann. Rept. U. S. Geol. Survey, 1888, 
pp. 418-423. and plate XLI. 
22. Report of Alexander Winchell. i6th Ann. Rept. Geol. and 
Nat. Hist. Survey of Minn., 1888, pp. 133-391. 
22,. Report of N. H. Winchell. Ibid., pp. 13-129. 
24. Report of N. H. Winchell. 17th Ann. Rept. Geol. and Nat. 
Hist. Survey of Minn., 1889, pp. 5-74. 
25. Report of H. V. Winchell. Ibid., pp. 77-145. 
26. Report of'Uly. S. Grant. Ibid., pp. 149-215. 
27. Some thoughts on eruptive rocks with special reference to those 
of Minnesota, N. H. Winchell. Proc. Am. Assoc. Adv. Sci., 1888, 37th 
meeting, 1889, pp. 212-221. 
28. The Taconic iron ores of Minnesota and of western New Eng- 
land, N. H. and H. V. Winchell. Amer. Geol., 1890, vol. VI, pp. 263- 
274. 
29. Record of field observations in 1888 and 1889, N. H. Winchell. 
i8th Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1891, pp. 7-27. 
30. The iron ores of Minnesota, N. H. and H. V. Winchell. Bull. 
6, Geol. and Nat. Hist. Survey of Minn., 1891, pp. 430; with a geological 
map of northeastern Minnesota. 
31. Notes on the petrography and geology of the Akeley lake region, 
in northeastern Minnesota, W. S. Bayley. 19th Ann. Rept. Geol. and 
Nat. Hist. Survey of Minn., 1892, pp. 193-210. 
2)2. Correlation papers — Archean and Algonkian, C. R. Van Hise. 
Bull. 86, U. S. Geol. Survey, 1892, pp. 51-208. See also, An historical 
sketch of the lake Superior region to Cambrian time, C. R. Van Hise. 
Jour, of Geol., vol. I, 1893, pp. 124-128. 
2,2,. Field observations o'n certain granitic areas in northeastern Min- 
nesota, U. S. Grant. 20th Ann. Rept. Geol. and Nat. Hist. Survey of 
Minn., 1893, pp. 35-95. 
34. The Mesabi iron range, H. V. Winchell. Ibid., pp. 126, 127. 
35. Nomenclature of the pre-Silutian rocks of Minnesota, N. H. 
Winchell. 21st Ann. Rept. Geol. and Nat. Hist. Survey of Minn., 1893, 
table on p. 5. See also pp. 143-152. 
Z(>. The geology of Kekequabic iakr. U. S. Grant. Ibid., pp. 29, 30. 
See also pp. 143-152. 
