Page:Report of the Second Norwegian Arctic Expedition in the "Fram," 1898-1902 (volume 4).djvu/191

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are not so ~lrong|y expressed or invariable as is demanded ol horizon tltﬂlx'tft'x two of the brauhiopods, chlwna rliomboidalis and Atrwa retituluris are wihtont any stratigraphir value. and therefore cannot be rnnsidered Accordingly. we have only the following lelt tor purposes of

correlation: 7

Tliecia sirimlerunmm GoLnr.

(‘Iotlopnro rcctilinea/a Sun’s.

liypirlzllu cov‘I/muueusis prognosticu Senora-tam: Spirifer I‘lllt14.tl'tlti HALL vat: prognostich ScHuanar, Iioa'oneutu [ilclii HALL.

Of these Tlieciu sn‘inderelmmi is a very widespread tormt cited from the Wenlock at Northern Europe and from the Niagara” of North America [MichiganY Tennessee-L It was found. however, by Professor Krcn ol Christiania Univers y occurring in the Norwegian Silurian in rocks at>o ot relathety high Ludlow age, in other words, it seems to he stratigraphirally no greatly restricted tossit. If we consider the other tour torms. we are dealing with species that as {or as is vet known.

have a very limited vertical di nbutioiL occurring in the horizon that is the large new monograph ot the Maryland Geological Survey. “The Lower Devonian of Maryland" is called the Keyser member of the 11 e I d e r h e r; g r o n p at that state and which corresponds to the Decker Ferry»Rondout-Manlius of New Jersey and the [Wilbur- ttosendate‘ﬂ-(Iobte. ill-Rondont-Manlins 0t eastern New York The three lll‘sl mentioned of these tour forms are very common in and

typical of this horizon. As mentioned in the dos ptive portion at this paper I have had an opportunity otrompaiing my Arctic specimens with Mo: tnrthermore been controlled by [’rote ‘ 'or Scimunzn'r, who knows the fauna

oi lilt' Ker

strongly supports this conclusion that we are dealng with an horizon

l:\iiiinply regard it as a nothern representative oi this form, The same

er Ferry of New Jersey and the Keyser of Maryland. that I

may be said ot the variety of Spiri/er modestus, a form belonging to the mosl‘typiral l{e}'>9t'-s[lk‘t'les.

\Ve have lltth reached an important result. in heng able to correlate ~ at any rate a greater part of — the Series B with a well-known hori- zon on the Ameriran Continent. It is not astonishing to ﬁnd that only