276 
Correspondence. 
county and at one outcrop in Audrain county, we have also noticed this 
coral. 
Occurring as natural casts in cherts of the upper Burlington beds, 
two miles north of Curryville, we have found excellent examples of 
Zaphrentis calceola associated with Granatocrinus norwoodi and Bat- 
ocrinus pyriformis. 
The examples of this variety are very much larger and less com¬ 
pressed than any of the lower forms, but easily recognizable from their 
peculiar rugose appearance. 
From the shales beneath the “Lithographic limestone” at Louis¬ 
iana, among other cyathophylloids collected, is one very much flat¬ 
tened example but with the basal point twisted to the side; and, though 
it is somewhat wrinkled, yet it bears but a faint resemblance to the 
Burlington form. 
There is little doubt in our mind that Zaphrentis calceola has de¬ 
scended in a direct line from the Corniferous species, Z. ungula and 
that it struggled upward through the Kinderhook, lower Burlington 
and “was gathered to its fathers” in the upper Burlington. 
A companion to Zaphrentis calceola in the lower Burlington at 
Louisiana, is Porcellia nodosa, a gasteropod described by Hall and 
recognized by Meek and Worthen as a Kinderhook species. 
The only (?) specimen of this species in the Illinois State Museum 
(found at Kinderhook, Pike Co., Illinois) was misplaced, some years 
ago, as we were informed by Prof. Worthen. If this was the type speci¬ 
men, the species now exists without a type. 
We have found but two examples of this fossil and both are natural 
casts in white chert, and both found some tenor fifteen feet from the 
base of the lower Burlington limestone. 
The third and last form under consideration is Batocrinus pistili- 
formis M. and W., described from a fragment and referred to the Kin¬ 
derhook group. 
As a natural cast in the upper Burlington chert, we have found ex¬ 
amples of this fossil not uncommon at Louisiana and even as abund¬ 
ant as B. pyriformis at Curryville. 
As casts the collector is perplexed to place this form, the calyx be¬ 
ing that of B. pyriformis while the dome is that of B. christyi. A cast 
in the mold settles the question and the fossil becomes B. pistiliformis 
with the arm openings directed outward instead of upward as in B. 
pyriformis. 
In an outcrop of upper Burlington limestone on Spencer creek, we 
found one body and a number of fragments of this crinoid, associated 
with Granatocrinus norwoodi var. cornutus, G. sayi and Batocrinus 
sequibrachiatus, well known upper Burlington forms. 
Curryville , Mo., March 1, 1889. R. R. Rowley. 
Foliation and sedimentation. The tone of portions of Prof. A. 
Winchell’s rejoinder published in the March number of the “ Geolo¬ 
gist ” is such that I would much rather drop the discussion of the 
