WaRD,] JURASSIC CYCADS FROM WYOMING. 403 
CYCADELLA CIRRATA Ward. 
Pls. CX-XTII-CXXIX. 
1900. Cycadella cirrata Ward: Proc. Wash. Acad. Sci., Vol. I, p. 272. 
Trunks of medium size, short-cylindrical, rounded at the summit, 
somewhat laterally compressed, unbranched; rock rather hard, drab 
on the weathered surfaces, dark within with white stripes, of medium 
specific gravity; organs of the armor ascending, especially above the 
middle toward the summit, as seen on the fractured surfaces, curving 
first upward and then gracefully outward in continuation of the clearly 
marked strands from the interior of the axis; leaf scars subelliptical 
or subrhombic, 12 to 15 mm. wide, 5 to 6 mm. high; leaf bases hard, 
dark, and porous; walls 3 to 5 mm. thick, hard and smooth, light 
colored or nearly white; reproductive organs few and obscure; armor 
3 to 5 cm. thick, irregularly joined to the axis; woody zone 2 cm. 
thick, undifferentiated; medulla 2 to 8 cm. in diameter, black, striped 
and blotched with white flinty patches. 
This species includes the specimens numbered 500.42, 500.46, 500.59, 
500.71, and 500.75, but they all probably belong to the same trunk. 
No. 500.46 matches No. 500.42 and No. 500.75 matches No. 500.46 by 
a narrow facet with the loss of intervening chips. No. 500.71 has 
exactly the same markings as No. 500.42 on the side opposite No. 
.500.46. These markings are too definite and peculiar to recur, and. 
amount to a proof of identity, although a thin plate between has dis- 
appeared. No. 500.59 is evidently the downward continuation of No. 
500.42. On one side there is almost complete continuity, but a large 
triangular piece is wanting on the other side. 
The specific name, from Latin cirrus, curl, refers to the beautiful 
curving lines and different-colored stripes formed by the various 
strands and organs of the armor as seen on the fractured surfaces. 
The weights of the pieces are as follows: 
Kilograms. 
NGS 00ME2 wes chet eta ised COC irl aaa ah ead ae 1.53 
NG 0046 sees So tenia haa peels os eet 0.57 
ING B00 50's seit daca tdaacie taeda wena setet te AL esl Li 
Nos 500/70) cacieyaic)svawtouscnug ncnuonaaaesian Serenade oe 0. 28 
ING? OOH ZB do ths inchs detaches cain anglais 0.70 
After all are put together we still probably have less than half the 
original trunk. 
In Pl. CX XIII (a to @) the four fragments Nos. 500.42, 500.46, 500.59, 
and 500.75, which all join by fractured surfaces or areas of contact of 
greater or less extent, are shown in their natural relations. No. 
500.59 forms the lowest part. No. 500.42 joins it above, reaching 
nearly to the apex. No. 500.46 joins No. 500.42 by a longitudinal 
