102 
AUG. F. FOERSTE 
The transverse striae are much finer and more crowded than 
those of Cyclonema daytonense Foerste,^^ from the same horizon 
and general area. Near mid-height of the last volution these 
striae form an angle of about 30° or 35° with the vertical axis 
of the shell. 
Locality and formation.^ — Found at Todd Fork, north of Wil- 
mington, Centerville, Dayton, Sharpsville, and east of Danville, 
Ohio, in the Brassfield formation. 
Remarks. — The only published figure of Cyclonema gyrone- 
moides is that found in volume,? of the Geological Survey of 
Ohio, on plate 37A, under the name Cyclonema hilix varicosum. 
This figure was based on a series of fragments of which the largest 
and most important consisted chiefly of the upper part of the 
last whorl, including the 5 prominent revolving ridges. The 
basal part of the last volution and the aperture were added from 
other specimens. This aperture evidently is that of a Cyclonema, 
and it remains to be shown that the species here described as 
Cyclonema gyronemoides possessed’ this type of aperture. At 
the time the figure was prepared numerous specimens of this 
species were at hand. Those recently collected do not show the 
aperture. In the published figure the spire appears to be much 
taller than in the specimens now at hand, possibly owing to the 
specimen being viewed from its narrowest aspect. However, 
here, again, there is a possibility of the apical part of the figure 
having been derived from some other specimen. In the speci- 
mens now at hand the spire is relatively depressed, somewhat as 
in the figure of Cyclonema daytonense published on plate 30 of 
the volume cited above, under the name Cyclonema hilix. Under 
these circumstances only the upper part of the last volution of 
figure 9 on plate 37A of the volume cited is to be regarded as 
unequivocally typical of the species Cyclonema gyronemoides; 
this part includes the 5 prominent revolving ridges. The re- 
mainder of the figure may be correct, but the specimens from 
which it was prepared have been lost, so that the accuracy of 
the remainder of this composite drawing can not be verified. 
Idem: pi. 30, fig. 15. 
