362 The American Geologist. June, 1904. 
The unusual feature to which attention is invited is the 
remarkable position which a band of fossils 4-6 inches thick 
assumes with reference to the concretions. Fossils are not 
generally distributed through the concretionary bed, and appear 
to be almost entirely absent except in a thin seam, 4-6 inches 
thick, belonging near the bottom of the concretionary zone. 
This band is composed almost entirely of common Chemung 
fossils ; but instead of following the horizontal direction of 
the tuiderlying strata it has in many places a sinuous course, 
corresponding to the base and sides of the larger concretionar}'^ 
masses. Where this band is present it separates the lower sides 
of the concretions sharply from the inferior beds, bearing much 
the same relationship to them that the outer shell of a nut bears 
to the inner. Not only does this fossil band follow the irreg- 
ular basal outline of the concretions, but frequently it bends 
abruptly upward, and, taking a vertical direction, follows the 
side of a concretionary mass as shown in the figures. 
•t7Ft 
Fig. 2. Showing sharp upward flexures of the fossiliferous band at 
the base of the concretions. 
It has been observed in at least one instance, as shown 
in fig. 3, after having followed around the base and side of 
a concretion, to be reflexed at the top and follow for a few 
inches the horizontal upper outline of the mass. 
It seems apparent from the remarkable relationship of the 
band of fossils and the concretions, that the commonly ac- 
cepted theory of chemical segregation is not alone a satisfac- 
tory explanation of the phenomena involved. The abnormal 
position of the zone of fossils filling the role of outer shell ta 
a concretionary mass seems to require. the action of some phys- 
ical agency for its explanation. The agency which disturbed 
the original horizontal position of this band must have acted 
