16 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 
[Puatre A. ] 
1. Polygonum tertiarium. 
Slender. Stem striate and somewhat angled, much enlarged and sparingly gnarled 
at the nodes, 4 mm. in diameter above the ocrea, 3.5 mm. above the node, and 8—9 mm. 
at the node; leaf lanceolate, entire, apparently acutish at the apex, sub-cordate at the 
base, petioled, the lamina 6 em. long, 2.6 cm. broad, apparently slightly undulate, the 
midrib about 1.5 mm. broad at the base, the secondary nerves opposite or alternate, 
leaving the midrib at angles varying from 40 to 45 degrees, soon curving upward, camp- 
todrome, sometimes coalescing at a point about half way to the margin or forking a short 
distance from the midrib, joined by tertiary cross-nerves, which leave the secondary one 
at almost a right angle; petiole 2 em. long, 1.5 mm. broad at the junction with the 
lamina, somewhat expanded and 4 mm. broad at the base, joined above the middle of the 
ocrea; ocrea cylindric, 3 cm. long, irregular at the summit. 
In the Miocene Tertiary at Florissant, Colorado. 
