216 Cincinnats Society of Natural Fitstory. 
which the leaves are an inch or more in length, broadly triangular 
in outline, coarsely toothed at the summit, which is more or less 
deeply bilobed. It occurs in the upper half of the Coal Measures, 
somewhat rarely in Pennsylvania and Ohio, more abundantly in 
Ilinois. 
Several other species of Sphenophyllum have been described by 
Lesquereux and White and Fontaine, but I have not had an op- 
portunity of studying them from the specimens themselves. 
In 1887, Dr. Dionys Stur, Director of the Geological Survey of 
Austria, published his ‘‘ Flora der Schatzlarer Schichten”’ in which 
he claims that the genera Asterophyllites and Sphenophyllum were not 
distinct and both were the foliage of Calamiles. And in January, 
1890, Mr. A.C. Seward, F. G. S., of St. John’s College, Cambridge, 
sent a paper to the Manchester Literary and Philosophical Society 
with the title ‘‘ Sphenophyllum as a Branch of Asterophyllites.” 
This paper was subsequently published in the Memoirs and Pro- 
ceedings of this society. Mr. Seward agrees with Dr. Stur that 
Asterophyllites and Sphenophyllum are parts of the same plant, but 
considers it not proven that they are the twigs and leaves of Cala- 
mites. He also questions the explanation offered first by myself 
and subsequently by Coemans and Kickx, that the difference be- 
tween the wedge-shaped and filiform leaves on the same plant was 
due to emergence and submergence, and quotes Schimper [ Hand- 
buch der Palaeontologie] as stating that the absence of intercellu- 
lar spaces in the stem of Sphenophyllum negatives the usual expla- 
nation that the finely dissected leaf form is the result of modifica-: 
tion brought about by submersion. But my specimens seem to 
fully confirm my views of the difference as expressed in 1853. In 
these only the upper branches have the wedge-shaped leaves, the 
lower portions of the plant being all furnished with those that are, 
capillary or acicular; precisely the difference that we find in Ca- 
bomba, Ranunculus and other aquatic, but not completely sub- 
merged plants. I therefore contend that this explanation is not 
only the most natural and plausible, but the only comprehensible 
one. 
Sphenophyllum was closely allied to Annularia and this was cer- 
tainly aquatic, for I have seen a rock surface six feet square com- 
pletely covered with the slender branches and discoid verticils of 
leaves which must have floated on the surface of water. 
