432 University Geological Survey of Kansas. 
it differs from the specimens described by Zeiller. The fine- 
grained sand in which the fossil is embedded had partly filled 
the hollow before the organ became compressed. The specimen 
has a radius of 8144 cm. The main ribs are thicker and stand 
out more prominently than those of the specimen from the 
French Coal Measures, although otherwise the two specimens 
agree closely except for the apparent lack of symmetrical de- 
velopment in the European specimens which Zeiller has so well 
described and illustrated. 
The numerous specimens from the Elmdale formation which 
Mr. White has kindly offered for study present considerable 
variation from this type and from each other. In size they 
vary from a few centimeters to probably not less than 30 cen- 
timeters when complete. The number of ribs at the base varies 
from three to six. The border has the appearance of being 
drawn out to a very thin edge, and it is in many cases im- 
possible to trace it to its termination. The most interesting 
character in connection with these specimens is a certain pit- 
ting and marking of the surface which resembles very much the 
impressions left by sporangia. The pits have the appearance 
of medium-sized sporangia arranged in a circle about an ele- 
vated central point of attachment much like that of a number 
of Marrateaceous ferns. Unfortunately the preservation is not 
such as to clear up all doubts regarding these impressions; 
they are, however, entirely similar to those left by sporangia 
in a matrix of this nature. A careful search has been made 
for spores retained in place within the sporangia, but without 
success, as the sandy nature of the matrix hardly permits the 
preservation of spores in mass within the sporangia. A bit of 
the surface removed to a microscope slide was found in one in- 
stance to contain a large spore, the reference of which, how- 
ever, to this plant could not be established. 
If the pittings on the surface subsequently prove to be im- 
pressions left by sporangia a considerable advance will have 
been made in the attempt to understand this entirely enigmatic 
fossil. Zeiller’s conception of the organ is that it is probably 
made up of six cuneiform leaves united by their lateral edges: 
It seems also possible that the organ is simply one large peltate 
frond or leaf with the petiole attached at the center, a hypothe- 
sis that would more readily account for the variable number . 
and arrangement of the main ribs. 
