Magnesian Limestones of Missouri.—Keyes. 385 
before going to the printers, it was not thought feasible to in- 
terrupt the printing by incorporating matter that was new, 
yet incompletely studied However, a paragraph on the gen- 
eral conclusions was inserted at’the last moment in the chap- 
ter on stratigrapiiv. It was planned to soon issue a special 
volume on the Cambrian fossils. ‘ 
At the time of the appearance of the general summary of 
the Paleontulogy of Missouri the following conclusions re- 
garding the Cambrian of the region were stated: “The geol- 
ogical age of the Paleozoic formations of Missouri, from the 
top of the column down to the base of the Trenton limestone, 
has been determined satisfactorily. Below the calcareous di- 
vision last mentioned is a great thickness of dolomitic lime- 
stones, with intercalated sandstone beds. These form what 
is commonly known as the ‘Magnesian limestone’ series. The 
lithological characters are very different from those of any 
of ihe later calcareous beds. Heretofore, fossils have not 
been fv.und abundantly in these formations; yet recent obser- 
vations have indicated that extensive faunas will be disclosed 
before long in the. rocks under consideration. Although it 
has been long known that the Magnesian limestones are 
older than the Trenton, and that they lie immediately upon 
and against the Archean crystallines unconformably, their ex- 
act geological age has always remained unsettled. There 
seems to be but little doubt, however, that part of the sequence 
is equivalent to the Calciferows of other regions. It is also 
pretty well determined thai certain of the lower beds, all below 
the ‘Sacharoidal sandstone’ perhaps, are representatives of the 
Upper Cambrian or Postdam. These conclusions appear well 
grounded beth upon stratigraphical and faunal evidence. The 
rocks of the Ozarx region have not as yet received the neces- 
sary detailed study to enable the several lines of terrane de- 
markation to be drawn.with certainty. This investigation is 
now being carried on as rapidly as possible, and promises 
very satisfactory and interesting results in the near future.” 
The actual evidence upon which the above quoted statements 
were made was very much more extensive and conclusive than 
that adduced by Beecher a decade later*, as reference to the 
“Missouri Paleontology” plainly shows. Not only were all his 
* Am. Jour. Sci., (4), vol. xii, pp. 462-463, 1901. 
