WARD.] JURASSIC CYCADS FROM WYOMING. 393 
to show the full length with a power of 90 diameters. The manner in 
which the chaffy hairs protrude from the armor and pour over the 
surface of the trunk, upon which they lie in mats of wavy lines, is 
shown on Pls. XCIV and XCV, illustrating C. Knowltoniana. The 
phenomena will be more fully described under that species. 
I am indebted to Dr. F. H. Knowlton for the drawing of Pl. LXX, 
made from slides of the two species, C. Knowltoniana (Figs. 1-3) and 
C. ramentosa (Figs. 4, 5), under the compound microscope. For 
further details see description of that plate. 
CycaDELLA ReEpi Ward. 
Pl. LXXI-LXXVI. 
1900. Cycadella Reedit Ward: Proc. Wash. Acad. Sci., Vol. I, p. 264, pl. xv. 
Trunks small (8 to 12 cm. high, 6 to 16 cm. in diameter), subspheroidal 
or subconical, unbranched, usually more or less laterally compressed, 
the axis oblique; rock substance rather soft, light colored, of low spe- 
cific gravity; organs of the armor ascending; leaf scars arranged in 
rows around the trunk nearly at right angles to the axis, subrhombic, 
15 to 20 mm. wide, 6 to 10 mm. high; leaf bases porous; walls 1 to 3 
mm. thick, hard and fine-grained, often flinty, usually white and some- 
what striate; reproductive organs very obscure; armor 1 to 3 cm. 
thick, separated from the axis by a definite line; wood 2 to 8 cm. 
thick; cortical parenchyma 1 to 2 cm. thick; fibrous zone divided into 
two or three rings of fine, more or less distinctly radiate structure; 
medulla 2 to 4 cm. in diameter, nearly circular, consisting of fine- 
grained homogeneous. tissue. 
To this species are referred five of the specimens. One of these, 
which is taken as the type, is the more complete of two originally sent 
to Professor Marsh by Mr. W. H. Reed, for whom the species is named. 
It is No. 127 of the Yale collection. The other specimens are Nos. 
500.6, 500.10, 500.19, and 500.29 of the Museum of the State University 
of Wyoming. The Yale specimen is larger than any of the others, 
weighing 2.04 kilograms, while No. 500.10 is the smallest trunk in 
either collection and weighs only 0.37 kilogram. No. 500.6 weighs 
1.48, No. 500.19, 1.56, and No. 500.29, 1.67 kilograms. 
Pl. LXXI represents the best side of the Yale specimen, with the 
eccentric medulla projecting. Pl. LX XII shows the side opposite this, 
which is considerably obscured by remains of the outer coat. Pl. 
LXXIII, Fig. 1, shows a side view of No. 500.29, of the Museum of the 
University of Wyoming, and Fig. 2 is a view of the base. Pl. LX XIV 
gives two views of opposite sides of No. 500.6, the base being faintly 
visible in both. Pl. LXXV, Fig. 1, represents the best-preserved 
side of No. 500.19, and Fig. 2 the base. Pl. LX XVI shows the two 
opposite broadest sides of the small No. 500.10. 
