Faiinal Aspects of the Original Kijiderliook.—Keyes. 319 
r.re of interest. He says: "If it be true tnat bed No. 4 is the 
northern extension of the Louisiana hmestone, then the Chon- 
opectus sandstone and the underlying shales would be includ- 
ed in the Devonian according to Keyes' interpretation of the 
Kinderhook." 
Now '"bed No. 4" is the Productal limestone. It is above 
what in the Iowa and Missouri reports has been regarded as 
the Hannibal shale, and if the most recent and detailed strati- 
graphical evidence* is to be relied upon, it is very near the top 
of the Kinderhook, instead of at the very base of that forma- 
tion. According to the statement just quoted, the Chonopec- 
tus sandstone, which immediately underlies the Productal 
limestone or is separated from it only by a very thin Coralline 
zone, would then be parallelled with the shales underlying the 
basal member of the Kinderhook (or Louisiana limestone), ai 
the type locality of that formation. However, there are grave 
difficulties to overcome before this opinion is fully substan- 
tiated, and Weller refers specifically to no data from which his 
inferences are drawn. 
Concerning the geological positi<jn (jf the Chonopectus fau- 
na alone Weller farther remarks: "Taken as a whole a large 
number of the total 81 species recognized in the fauna, have 
Devonian and not Carboniferous relationships, but this is not 
-sufficient evidence upon which to establish the Devonian age 
of the fauna. In general, in paleontologic interpretation, the 
initiation of a new invertebrate faunal element is of greater 
importance' than the holding over of a much larger element 
from an older fauna, and on this principle the strongly Carbon- 
iferous element among the brachiopods of the Chonopectus 
sandstone is to be considered as weightier evidence than the 
holdover pelecypods and cephalopods." f 
Of the six zoological classes of organisms, which the 81 
emimerated species go to make u]), all but the brachiopods 
have admittedly a strong Devonian aspect. Of the score of 
brachiopod species one-half are certainly indecisive as to ex- 
act age, and of the other half there is about ecjual division be- 
tween Carboniferous and Devonian types. There is therefore 
*Joiirnal (iet)logy, V'ol. \'III, p. 317, iqoo. 
tTrans. Acad. Sci., .St. Louis, Vol. IX. p. r26, 1900. 
