XXXV1 THE PALEONTOLOGY OF MINNESOTA. 
J. H. Kloos. 
1871. Geologische Notizen aus Minnesota. By J. H. Kuoos. Zeitschr. d. Deutschen 
geologischen Gesellschaft, Jahrg. 1871. (Translation in the Tenth Annual Report of the 
Minnesota Survey, 1881). 
Geognostische und geographische Beobachtungen in Staate Minnesota. J. H Koos. Zeitschr. 
d. Gesell. f. Erdkunde zu Berlin, Bd. x11, 1877. (Translation in the Nineteenth Annual 
Report of the Minnesota Survey, 1890). 
The foregoing are titles of papers based on observations and collections made by Mr. 
Kloos during a sojourn in Minnesota before the commencement of the present survey. Of 
the Lower Silurian strata at St. Paul he mentions, in the former, the following species: 
Orthis tricenaria Con. and O. testudinaria Dalm., Leptcena sericea Sow., Murchisonia bicincta, 
Bellerophon bilobatus Sw.; ‘all characteristic shells of the Trenton, and partly also of the 
Llandeilo flags of England.” In higher layers he mentions the following: Rhynchonella 
recurvirostra H., and R. increbescens H., Petraia corniculum H., Stenopora fibrosa Goldf., 
Calymene senaria (blumenbachii), and Ptilodictya sp. ‘‘fossils which altogether have been 
assigned to the Trenton by Logan in Canada.” 
In the latter paper, besides the above, he mentions the following, at the same place: 
Strophomena alternata Con., (the ‘‘ Producti” of W. H. Keating and others), Ctenodonta 
nasuta Hall, Leperditia fabulites, Plewrotomaria lenticularis Con., Subulites elongata Con., 
Orthoceras junceum Hall, Buthotrephis succulens Owen, Palewophycus rugosus, Strophomena 
deltoidea Con.,,and Schizocrinus nodosus Hall. He objects to Hall’s statement that at this 
place the different members of the Trenton, as displayed in the eastern part of the United 
States, can be distinguished: ‘So far as Minnesota is concerned this must be wholly 
erroneous,” * * * ‘The fossils taken together point to the level of the proper Trenton 
limestone, and some extend much higher, in the Hudson River group, though they are not 
found in the lower beds in the eastern states.” 
W. D. Hurlbut. 
1871. Geology of Southern Minnesota, by W. D. HurLBuT, in The Minnesota Teacher, 
Jan., Feb., March, April, May, 1871. (Vol. IV). 
Mr. Hurlbut was the first to direct public attention to the geology of the southern por- 
tion of the state, remote from the Mississippi valley. He based his observations upon a 
careful study of the stratigraphy of Owen. He stated that the Lower Silurian rocks form 
the surface over an area of about 6,000 square miles in the southern part of the state. He 
worked out their stratigraphy, specially along Root river and its branches, giving dia- 
grams illustrating their position and thickness, but without the aid of fossils. The green 
shales overlying the Trenton (7. e. Buff limestone) he called Hudson River oil shales, and 
the alternating beds of shale and limestone (7. e. the transition from the Trenton to the 
Galena) still higher he regarded as Clinton. The Galena limestone he considered of 
Devonian age, probably Corniferous, although he here mentions Maclurea and ‘other 
