a4 
as 
warRD.] JURASSIC CYCADS FROM WYOMING. 415 
The specific name has a vague reference to the Freezeout Hills, in 
which the beds occur. 
Pls. CLXV and CLXVI are side views of the opposite side of No. 
500.1, and Pl. CLXVII is a view of its base. Pls. CLXVIII and 
CLXIX show the opposite sides of No. 500.24. 
CYCADELLA CARBONENSIS Ward. 
Pl. CLXX; Pl. CLXXI. 
1900. Cycadella carbonensis Ward: Proc. Wash. Acad. Sci., Vol. I, p. 282. 
Trunk of maximum size (89cm. high, 21 by 39cm. in diameter), 
subglobular, both laterally and vertically compressed, the principal 
axis oblique to the plane of compression, having numerous secondary 
axes forming large short branches or rounded elevations interspersed 
with smaller ones, the primary axis terminating in a well-developed 
bud, the base occupied by a circular concavity; rock of medium hard- 
ness and specific gravity, nearly black, considerably mineralized in the 
interior; organs of the armor radiating from an equatorial zone; 
phyllotaxy not traceable; leaf scars subrhombic, rhombic, or irregular 
in shape, 30 mm. wide, 15 mm. high; leaf bases rough and porous; 
walls 2 to 3mm. thick, firm, and definitely bounded, longitudinally 
striate with raised white lines, median line higher than the rest; 
reproductive organs numerous but not well developed, of two kinds, 
large and small, the former difficult to distinguish from secondary 
axes, all usually more or less elevated, but occasionally depressed or 
decayed so as to leave a shallow concavity, elliptical in cross section, 
the larger ones 3 by 5cm. in diameter, the smaller about half as large, 
the former class surrounded by faintly visible large subrhombic invo- 
lucral bract scars simulating and passing into leaf scars, the central 
portions solid and heterogeneous; armor 4 to 5cm. thick, its junction 
with the axis obscure; woody zone 4 to 5 em. thick, qniceorentited: 
medulla nearly circular, 5 to 6 cm. in diameter, smooth and homo- 
geneous in structure. 
The largest specimen in the collection, No. 500.2, weighing 37.69 
kilograms, is unique also in its form and a considerable number of 
other characters, and has to form a species by itself. I name it for 
Carbon County, in which the locality for all the specimens is located. 
It constitutes an almost complete trunk, but came in two nearly equal 
pieces, the fracture passing through the narrowest dimension, through 
the center of the apex, down the back and lower side, and emerging at 
the center of the basal concavity along a nearly even plane. Unfor- 
tunately, the interior thus exposed shows scarcely any structure. 
Pl. CLXX shows the broad rounded back of the specimen, and Pl. 
CLXXI the base and lower portion. 
