knowlton.] DESCRIPTION OF SPECIES. 65 
blade, from which point it is regularly wedge shaped to the apparently- 
sessile base. The nervation consists of a thin, somewhat flexuose mid- 
rib, which has some three or four very thin, often forking, branches, a 
copious fine nervation of minute quadrangular areolae. 
It is with some hesitation that I venture to describe this as a new 
species, but it appears to differ in essential characters from the well- 
known T. f microphylla. The latter is always rounded to the truncate 
base, and has very minute denticulations above. The one under con- 
sideration is strongly wedge-shaped at base and has large obtuse or very 
obtusely pointed teeth. I have seen nothing intermediate between 
these two forms, and have therefore described it as new. It is obvi- 
ously very closely related to T. f microphylla, particularly in the finer 
nervation. 
Habitat. — Point of liocks, Wyoming. 
PODOGONIUM AMERICANUM Lx. 
Podogonium americanum Lx., Tert. Fl., p. 298, PI. LIX, fig. 5; PI. LXII1, fig. 2; PI. 
LXV, fig. 6 (1878); Cret. and Tert. FL, p. 202 (1884); Ann. Rept. U. S. Geol. and 
Geog. Surv. Terr., 1876, p. 519 (1878). 
Podogonium sp. Lx., Ann. Rept. U. S. Geol. and Geog. Surv. Terr., 1873, p. 417 (1874). 
Two of the type specimens of this species as figured by Lesquereux 
are preserved in the United States National Museum (No. 485, original 
of PI. LIX, fig. 5, and No. 581, original of PI. LX1II, fig. 2). The orig- 
inal of PI. LXV, fig. (J, is not and, so far as the records show, has never 
been in the Museum collection. 
The first of the above-mentioned specimens (No. 485) is said to have 
come from Black Buttes, Wyoming, and is so recorded in the Museum 
register. As it is preserved on the hard, red, baked shale well known 
to be characteristic of a certain horizon at this locality, this statement 
is undoubtedly correct. The other example (No. 581) is recorded in the 
Tertiary Flora (p. 299) as having come from Middle Park, Colorado, 
while in the Museum register it is recorded as coming from Point of 
Kocks, Wyoming. A glance at the matrix is sufficient to show that it 
could not have come from any recognized locality in Middle Park, 
while on the other hand it is similar to material from Point of Rocks. 
The surmise that it must have come from Point of Kocks is still further 
strengthened by the fact that preserved on the same stone with it is 
one of the figured specimens of Ficus dalmatica Ett., a species that is 
only recorded by Lesquereux 1 from Point of liocks. It is, therefore, 
without doubt safe to assume that it came from this locality and not 
from Middle Park. 
As already stated, the other figured specimen can not now be found, 
and it is altogether probable, judging from the figure, that it does not 
belong to this species. It has, it is true, the same shape, but appears 
to have been a thicker leaf with a quite different nervation. It has 
1 Tert. FL, \>. 199 (1878). 
Bull 103 5 
