256 BOTANICAL GAZETTE. [Oct., 
habitat this should be, in its cleistogamous-flowering summer 
state, the V. clandestina of Pursh. 
uP III. Subcaulescent by leafy stolons, or caulescent, with ascending 
2-3-leaved stems, slender, almost glabrous, multiplying by long filiform root- 
stocks: leaves all reniform or cordate, undivided: corolla a bright yellow, 
with saccate spur: stigma terminal, beardless and beakless. 
V. sarmentosa Dougl. To this belongs V. rotundifolia Hook. 
in Lond. Jour. Bot. vi. 73, in Geyer’s collection, a species which 
it considerably resembles at first, flowering direct from the root- 
stock. 
V. biflora L. Always caulescent, no leafy stolons; stigma 
margined on two sides. In this country known only from the 
Colorado Rocky Mountains; in the Old World ranges from 
Kamtschatka and Japan to Europe. 
Synopsis of North American Pines, based upon leaf-anatomy.’ |. 
“\ JOHN M. COULTER AND J. N. ROSE. 
(WITH PLATE VIII.?) 
_ The genus Pinus is very naturally circumscribed, but its spe- 
cies have always been notably difficult of discrimination. This 
1Read before the A. A. A. S., Buffalo meeting, 1 
, 1886. i 
7EXPLANATION OF FIGURES.—1. P, Strobus, 2 dorsal peripheral ducts, stomata oD ventral 
s,and single fibro-vaseular bundle, M54: 2p Gauss, P parenchy mets ducts, stoma 
on all faces, fibro-vaseular bundles, X54: 3. P. sis, internal duct, - 
eaten ue sole of aoe bundle-sheath with thick outer walls, K250 ; 4 
lg ; - 2. ening ceils next the epidermis, ys 
. P. flerilis, thin-walled layer (pitted) net th ; . tubereulata, 
walled layer between epidermis and stengtennien ae re eae af 
