218 
sionally widening somewhat medianly and less 
acutely pointed, separated by generally open 
and rounded sinuses extending about halfway 
to the base. The angles that the lobes form 
with one another and the form of the sinuses 
vary with the number of lobes, as does also the 
character of the base, which ranges from trun- 
cate to decurrent. The median lobe is gen- 
erally slightly wider than the others but may 
. be smaller. The normal form is five lobed 
like the smaller of the two specimens from the 
Cheyenne sandstone here figured. The texture 
is so coriaceous that these leaves are well pre- 
served in the scarcely consolidated wind-blown 
sand of the Cheyenne. The margins are entire. 
Length from 8 to 20 centimeters; maximum 
width from 6 to 24 centimeters. Petiole stout, 
usually broken away, 12 centimeters long in a 
medium-sized leaf figured by Lesquereux. 
Midrib stout, channeled, prominent on the 
under side of the leaf. An equally stout lateral 
primary diverges from the midrib, usually at 
‘its extreme base but occasionally slightly 
above. In the five-lobed forms this primary 
forks almost immediately into two subequal 
branches, which form the midveins of the respec- 
tive lobes. In specimens having more than five 
lobes the additional ones are subordinate to 
the basal laterals, their midveins diverge at an 
acute angle from the midveins of these laterals, 
and their separating sinuses are less deep. The 
secondaries are thin and immersed in the leaf 
substance and are largely obsolete in the Chey- 
enne sandstone specimens; they are numerous, 
regularly spaced, subparalleled, and campto- 
drome in the lobes and in curved anastomosing 
loops in the body of the lamina. 
This is an exceedingly well marked species 
and, like most Sterculias, both ancient and 
modern, shows the characteristic variability of 
the genus. 
material collected in the Dakota sandstone of 
Kansas and occurs in the Big Tucumcari 
Mountains of New Mexico in beds referred to 
the Dakota. It is recorded from the Magothy 
formation of Massachusetts and New Jersey. 
In the Cheyenne sandstone of Kansas it occurs 
at these localities: Black hills near Belvidere 
(773); Osage Rock, Belvidere (2217); Stokes 
It was described originally from. 
SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1921. 
Hill, 100 yards south of the National Corral 
(2219); Thompson Creek near the flume, 2 
miles northwest of Belvidere (2221); near 
Medicine Lodge Creek, 2 miles west of Belvi- 
dere (2224); left bank of middle branch of 
Champion (Wildcat) Draw, half-a mile south 
of Belvidere (2229); draws north of Belvidere, 
in “Lanphier shales’” (2230); Osage Rock, in 
“Stokes .sandstone”’ (2232); Wildcat Draw 
(7405). 
Sterculia mucronata Lesquereux. 
Sterculia mucronata Lesquereux, U. 8. Geol. Survey Mon. 
17 (Flora of the Dakota group), -p. 182, pl. 30, figs. 
14, 1892. 
Leaves coriaceous, ee small, pal- 
mately three tofivelobed. Lobesentire, conical, 
separated by open rounded sinuses extending a 
variable distance, sometimes over halfway to 
the cuneate or truncate base. Petiole long and 
stout. Primaries three from the top of the 
petiole, stout and prominent. In the five- 
lobed. forms subordinate branches from the 
lateral primaries furnish these with midveins. 
Secondaries thin, camptodrone: The tips of 
the lobes are prominently mucronate, and this 
feature, which suggested the specific name, is 
especially obvious:in the Cheyenne sandstone 
specimens, where the mucros are 2 millimeters 
long and perhaps merit the designation eaep ls 
date rather than mucronate. 
The fact that these leaves are prevailingly 
small suggests that they probably represent 
small leaves of the associated Sterculia towneri, 
with which they agree in their main features— 
the mucronate tips of S. mucronata being the 
principal differential characteristic. The leaves 
originally described were obtained from the 
Dakota of Ellsworth County, Kans., and the 
species is known only from that region and the 
Cheyenne sandstone of southern Kansas, al- 
though there is a similar but distinct species, 
Sterculia minima Berry,* in the Magothy formas. 
tion of New Jersey and Maryland. Two speci- 
mens were found in the Cheyenne sandstone 
near Medicine Lodge River, 2 miles west of 
Belvidere (2224). 
33 Berry, E. W., Maryland Geol. ce. Upper Cretaceous, p. 857, 
pl. 80, figs. 1-3, 1916. 
