78 Order CARYOPHYLLACEA# 
12. Anychia. 404. 
1. Anychia canadensis (L.) B. S. P. Forked Chickweed. 
In woods in the southeastern part of the state. Nehawka; Weeping 
Water. 
2. ELATINACEZ. 
Elatine. 629. 
1. Elatine triandra Schk. Mud-purslane. 
In shallow water in ponds or creeping on muddy banks. Exeter. 
3. SALICACE. 
Willow Family. 
Flowers subtended by fimbriated or incised bracts; stamens usually 
numerous; dise large, cup-shaped. 1. Populus. 
Flowers subtended by entire bracts; stamens usually few, often two; 
disc minute. 2. Salix. 
1. Populus. 308. 
Leaves not much longer than wide. 
Petiole terete. 1. P. balsamifera. 
Petiole flattened. 
Leaf-blades broadly deltoid or cordate, abruptly long acuminate. 
4, P. sargentii. 
Leaf-blades suborbicular, acute or short acuminate. 
5. P. tremuloides. 
Leaves at least twice as long as wide. 
Leaf-blade three times as long as the petiole, not long acuminate. 
2. P. angustifolia. 
Leaf-blade not more than twice as long as the petiole, abruptly 
long acuminate. 3. P. acuminata. 
1. Populus balsamifera L. Balsam Poplar. 
Rare in the canyons of the Hat Creek basin. 
2. Populus angustifolia James. Narrow-leaved Cottonwood. 
Rare in the Hat Creek basin. Sioux and Scotts Bluff counties. 
3. Populus acuminata Rydb. Black Cottonwood. 
Rare in the northwestern part of the state. Gering. 
4. Populus sargentii Dode. Western Cottonwood. 
Populus occidentalis (Rydb.) Britton. 
Common along streams all over the state. Lincoln; Red Cloud; 
Stuart; Thedford; Valentine. 
5. Populus tremuloides Michx. Aspen. 
Common in canyons in the northwestern part of the state. Hat 
Creek basin; Valentine. 
2. Salix. 310. 
Willows. 
Leaves distinctly serrulate, or if entire linear or linear-lanceolate. 
Leaves glossy as if varnished above, broad, stipules glandular. 
3. S. lucida. 
Leaves not glossy, often narrower. 
Leaves finely and closely serrulate. 
