1100 General Notes. 
dentally kept back by a breakdown and the storms, now just ready 
to sail for Copenhagen, and we send two messengers, hoping they 
will reach the steamer, and perhaps make it wait for us and take 
us home. We have but very little hope, though, that the steamer 
will wait, and we shall be compelled to stay here over winter, as 
this is the last chance this year.” 
It appears that the steamer did not wait for them, but 
took the letters and delivered them at Farsund, the nearest 
ort in Norway. The expedition, consequently, must stay in 
Greenland through the winter, with the prospect of getting 
lenty of leisure time, and next summer we shall have a 
full report of this remarkably daring and interesting journey. 
GEOLOGY AND PALAONTOLOGY. 
DESCRIPTION oF NEw AND IMPERFECTLY KNOWN SPECIES 
OF BRACHIOPODA, FROM THE Devonian Rocks or IOWA —O 
the Brachiopod Fauna of the Devonian rocks of Lowa, no genus 15, 
perhaps, so variable as the Genus Atrypa. Many varieties of 
Atrypa recticularis, of the Iowa strata, are often restricted in their 
range to certain horizons and localities. For example, at lowa 
City, Turkey Creek and Roberts’ Ferry, in Johnson county, there 
occurs in a bed of argillaceous shale a very large and coarse vari- 
ety of this species, which is not known to appear at any other lo- 
 cality in Iowa, or elsewhere. In some dark bituminous shale at 
Independence, occurs another variety of the same species, an which 
is analogous to one of the varieties of the Rockford shales; this 
form, however, differs from the Rockford shale variety in its very 
diminutive size. : 
In the limestone at “Big Bend” of the Iowa river in Johri 
county, at Independence, Waverly, etc., occurs another well-marke 
variety. Many individuals of this variety s very large thin 
wings or expansions, the entire shell having a diameter of from five 
to eleven centimeters; the body of the shell, however, being often 
only one-half or even one-third that diameter. i 
At Littleton, in Buchanan county, is found another very pane 
variety (a coarse form) whose equivalent is not known to occur & 
any other locality in the State; its nearest representative, § K 
known to me, occurring in the Devonian strata at Louisville, 4s A 
In the Rockford shales occur two varieties, the smaller of per 
has the front of the shell so strongly contracted as to produce a %15- 
