The X if/hru m ('/in//,-. — ('nl rin. 14 i 
enough for macroscopic study were comparatively few in 
number both as to individuals and species, microscopic life of 
wonderful beauty and of the highest scientific- significance was 
developed in incomprehensible profusion. The characteristic 
faunas and the floras of the Niobrara must lie studied with 
the microscope. 
Hesitancy ok American geologists to recognize the 
NlOBRABA DEPOSITS AS ChAI.K. 
Before discussing the microscopic life of the Niobrara age, 
it may be worth the while to notice an interesting mental 
attitude of leading American geologists to the question of the 
existence of chalk on this side of the Atlantic. Notwithstand- 
ing the fact that the earliest travellers up the Missouri river. 
and every one who has since followed in their footsteps, must 
have been convinced that the beds in question present, out- 
wardly at least, all the physical characteristics of chalk, and 
notwithstanding the further fact that professor Bailey point- 
ed out the foraminiferal origin of the material as long ago as 
1841, there yet grew up a very firmly rooted notion that the 
peculiar earthy material we call chalk is not found in any of 
the geological formations of this continent. For example, 
professor Dana, in the second edition of his Manual, speaks of 
the beds of sand, marl, and loosely aggregated shell limestone 
in the Cretaceous strata of America, but he adds with inten- 
tional emphasis that " they include in North America no 
chalk" In the third edition of the Manual the statement is 
modified so as t(t read that " they include in North America 
no chalk, excepting in western Kansas, where. :5.")(i miles wesl 
of Kansas City, a large bed exists." In the second edition of 
Le Conte's Elements of Geology we are told that chalk occurs 
■' nowhere except in Europe;" but in the third edition it is 
stated that " recently good chalk composed of foraminiferal 
shells, and containing flints, has been found in Texas." In 
the Geological Studies of Dr. Alexander Winchell, the author, 
after discussing chalk, tells us on page 64, that "it doe8 not 
occur in America ;" and the impression is thought to lie worl hy 
of repetition in nearly the same words on page 183. In the 
Canadian dfatumlist for 1S71 Dr. <;. M. Dawson has an arti- 
