332 WHITE—OMPHALOPHLOIOS, A NEW LEPIDODENDROID TYPE. 
in the original figure, though many are round and some are transversely 
oval. The lateral angles, as well as the short, vanishing, lateral furrows, 
are distinctly indicated in most cases, while generally the central trace 
in the roundish area is more or less clearly shown. ‘This is also true 
where the outermost cortical tissue still adheres to the matrix, even in 
the area represented by the shaded portion in the original figure. 
Another of the originals described by Lesquereux is a small slab, num- 
ber 5502 of the Lacoe collection, representing, like the other, a mold or 
impression of the stem. In a portion of this fragment, too, we have 
bolsters and inside areas like those in the originally figured type, num- 
ber 5501; but here we have also a variety of distortions, due to pressure, 
in which the central areas or compressed bosses often appear more than 
twice as wide as long, while in some cases they are partially covered on 
all sides by the infolded lateral areas about the flattened bosses. It may 
be noted in passing that the central areas in this fragment, photographed 
in plate 22, figure 3, are much broader in proportion to their altitude ~ 
- when the bolsters themselves are correspondingly dilated. In addition 
to these features, this specimen shows not only the central traces, but 
also in a few cases the obscure vertical furrows, which in several instances 
seem to unite below the upper margin of the central areas in a loop or 
long horseshoe, between the sides of which are the central traces. This 
character, as well as certain other more obscure details, will be considered 
in the description of the surface of the lately collected stems. 
DESCRIPTION OF ADDITIONAL SPECIMENS 
Another incomplete slab, about 25 centimeters wide, showing the 
mold or external impression of the stem, is partially illustrated in plate 
21, figure 3. In this specimen, chosen because it represents the more 
elongated bolsters with the central convex areas slightly displaced, we 
find in many of the latter the two vertical grooves, about 2 millimeters 
apart, passing across to the compressed boss and forming, as in the speci- 
men just described, a loop or elongated horseshoe, within which the vas- 
cular trace is seen in all cases to he. Occasionally a second trace is ob- 
served at the apparently open end of the horseshoe. The same interior 
characters are seen in Museum register 6030, another impression of a 
fragment with short squarish bolsters, illustrated in plate 22, figure 2. 
The specimens described above are all impressions or molds of stems, 
in some of which the epidermis may have been wanting. We will now 
proceed to the consideration of several segments of stems on which the 
cortex is still preserved. The first of these, Museum register 6029, is a 
flattened branch, nearly the full width of which is seen in plate 21, fizure 
