"te 
OF THE GENUS PINUS. 59L 
The leaves are in threes, each 3-sided, dorsum convex, without 
stomata, sides concave, with 4-5 rows of stomata, resin-canals 
marginal ; meristele elliptic or circular in section, with an 
unbranched vascular bundle. The number of the cotyledons 
varies from 3 to 8. 
24. Pinus cummuanuana, Engelmann ; Sargent, Silva, xi. 
(1897) p. 85, t. 566. 
This tree is a native of the mountains of Northern Mexico, as 
well as New Mexico and Arizona. The leaves are in groups 
of three, with median resin-canals. The endoderm-layer consists 
of 30-40 cells, and the circular or elliptical meristele comprises 
a branched bundle. The mesophyll-cells are. plicated. The 
sheaths are deciduous. The male flowers racemose. The ripe 
cones are oblong-ovoid or ovoid-conic, not unlike those of 
P. Laricio. The apophyses are flattish, grey, with the upper 
edge lancet-shaped. The umbo is depressed, at first mucronu- 
late. Engelmann notes that this species matures its cones only 
in the third year, a peculiarity which it shares with the Stone- 
Pine (P. Pinea) of the Mediterranean district. 
25. P. Lumuorrazu, B. L. Robinson §& M. L. Fernald, Pro- 
ceedings of the American Academy of Arts and Sciences, vol. xxx. 
August 27 (1894), p. 122; Scribner’s Magazine, xvi. p. 38. 
Of this species I have seen only incomplete specimens. It 
was collected near Coloradas in the course of an archeological 
expedition to N.W. Mexico. The pendulous leaves are said to 
be in groups of three with the sheaths quite obsolete. The cones 
were not seen. In section the leaves are three-sided, dorsum 
convex, sides concave. JResin-canal median. Meristele oblong 
in section. 
26. P. rwsunarts, Endlicher; F. Villar, in Blanco, Fl. Filip. 
ed. 3, Nov. App. p. 212, t. 453; Vidal, Sinops. Kam. y Gen. Pl. 
Lenos Filip., Atlas, t. 98. fig. C. 
A. species native of the Philippines, with long slender leaves, 
3 in a sheath, the scales of which are thin and membranous but 
persistent, the innermost are deeply fringed. In section the 
leaves are three-sided, with a convex dorsum and two concave 
lateral surfaces meeting anteriorly ina prominent ridge. There 
is a single layer of hypoderm, in contact with which are two 
resin-canals. The cells of the mesophyll have infolded walls. 
LINN, JOURN.—-BOTANY, VOL, XXXY. 2x 
