358 JOURNAL OF THE WASHINGTON ACADEMY OF SCIENCES VOL. 13, NO. 15 
Leaf blades ovate or oblong, 8 to 12 em. long, 4 to 5 em. wide, acuminate 
(acumen 1 em. long), rounded at base, finely sarrate (teeth obtuse), 3-nerved 
to apex (nerves depressed on upper surface, with numerous pairs of parallel 
secondary nerves along each primary nerve), the upper surface dark green, 
glabrous, bearing faint linear cystoliths, the lower surface paler, densely 
tomentulous on the nerves and veins, destitute of cystoliths but conspicuously 
punctate between the veins. Staminate cymes up to 15 cm. long, borne in 
pairs in the axils of the upper leaves, profusely dichotomous, the peduncles and 
branches densely tomentulous; bracts unusually large for the genus, white; 
calyx globose, 1 mm. in diameter, white proximally, dark purple distally, its 
lobes minute. Pistillate cymes subsessile in the axils of the lower leaves, 
shorter than the petioles; middle segment of perianth obovate, 1.5 mm. long, 
the lateral segments broadly ovate, 1 mm. long; achenes broadly ovate, 2 mm. 
long, the margin thickened. 
Type in the U. S. National Herbarium, no. 1,140,930, collected in a moist 
forest along the Rio San Rafael, below Cerro Tatama, Department of Caldas, 
Colombia, altitude 2,600 to 2,800 meters, September 7 to 11, 1922, by F. W. 
Pennell (no. 10380). 
This is allied to P. hirsuta Wedd., differing chiefly in its larger staminate and 
smaller pistillate inflorescences, in the prominent bracts subtending the 
staminate flowers, and in the closer serrations of the leaves. 
Pilea tatamensis Killip, sp. nov. 
Plants dioecious. Stem. repent, at length erect, simple or branching to- 
ward the summit, hirsute throughout. Stipules ovate-lanceolate, 7 to 9mm. 
long. Leaf blades flat or often slightly rugose, sharply serrate (teeth 2 mm. 
long), triplinerved (lateral nerves originating 3 to 4 mm. above base and 
extending to upper third of blade), the upper surface dark green, glabrous, 
bearing (except along nerves and veins) minute linear cystoliths, beneath 
paler, densely appressed-hirsute on the nerves and veins, sparsely airsute 
elsewhere, the cystoliths fewer and less conspicuous than on upper surface; 
leaves of a pair unequal and slightly dissimilar, the larger ovate or elliptic- 
ovate, 3 to 6 em. long, 2 to 2.5 em. wide, acute at apex, obliquely cuneate at 
base, the smaller ovate, 2 to 3 cm. long, 1 to 1.5 em. wide, rounded or subacute 
at apex, rounded or subcuneate and oblique at base. Staminate heads globose, 
1 cm. in diameter, pilosulous, densely flowered, the peduncles 1 to 1.5 em. 
long, hirsute; calyx lobes filiform, 2 to 2.5mm. long. Pistillate heads cymose, 
1 to 1.5 em. broad, glabrescent, the peduncles longer than the petioles; 
achenes ovate, 1 mm. long. 
Type in the U. 8. National Herbarium, no. 1,140,928, collected in moist 
forest along the Rio San Rafael, below Cerro Tatama, Department of Caldas, 
Colombia, altitude 2,600 to 2,800 meters, September 7 to 11, 1922, by F. W. 
Pennell (no. 10378; staminate plants). The pistillate plants are represented 
by Pennell 10375 (U. 8. Nat. Herb. 1,140,925). 
In habit and general aspect this plant resembles P. fallax Wedd. It is 
differentiated by larger leaves with two well-marked lateral nerves, by the 
arrangement of the cystoliths, by longer peduncles, and by the more elongate 
lobes of the staminate flowers. Since the leaves at a node are not conspicu- 
ously unequal, the species should probably be referred to the section containing 
the long-peduncled pubescent species. The globose staminate heads suggest 
