602 DR. M. T. MASTERS : GENERAL VIEW 
mose, the cones about 5 cent. long, ovoid-conic; apophyses flat, 
rounded or slightly pointed at the upper border ; umbo depressed, 
rhomboid mucronate. 
To this species I refer—Nelson 1!, gathered on Tolucca, and 
Donnell-Smith (Guatemala), 2633 & 3156! 
46. Prsus Torreyana, Parry, Bot. Mex. Bound. p. 210, tt. 58, 
59 (1859); Sargent, Silva, xi. (1897) p. 71, t. 557. 
A distinct Pine, very limited in its range, growing only, so far 
as is known, in South California, near the mouth of the Saledad 
River, along the coast and on Santa Rosa Island, 34° N. lat. 
For fine specimens of its cones I am indebted to Dr. Franceschi. 
The seedling plants observed at Kew are robust, with a long, 
tapering radicle, and a stout cylindric caulicle, with five resin- 
canals between as many vascular bundles. The cotyledons are 
about 12, linear, flattish, ‘The primary leaves are elliptic in 
section, pointed at the angles with a prominent keel. The 
resin-canals are median, the meristele elliptic with a branched 
fibro-vascular bundle. The adult leaves are 20-30 cent. in length, 
markedly triangular in section, stomatiferous on all sides. The 
hypoderm is in thick wedge-shaped masses in the intervals 
between the stomata. Cortical cells with infolded walls; resiu- 
canals median, surrounded by a stereome-sheath ; endoderm 
of about 40 cells, much thickened outwardly ; meristele trian- 
gular; fibro-vascular bundle branched, more or less completely 
surrounded by stereome-cells. The male flowers are in clusters, 
each 5-7 cent. long, surrounded at the base by as many as 14 or 15 
scales. The cones are subsessile, 13-15 cent. long, broadly ovoid, 
with very prominent apophyses and stout pyramidal umbos. 
47. P. artzonica, Engelmann, Sargent; Silva, xi. (1897) p. 75, 
t. 559. 
A five-leaved Pine, native of the mountains of Southern 
Arizona, at altitudes of 7000 feet. 
The leaves are three-sided, with stomata on all sides, with a 
double layer of hypoderm thickened at the angles. The cells of 
the mesophyll have infolded walls. The resin-canals are median, 
surrounded by a stereome-sheath. The endoderm consists of 
35-40 cells much thickened on their outer walls. The section of 
the meristele is triangular, with somewhat truncated angles. 
The fibro-vascular bundle is branched, the branches surrounded 
by many stereome-cells. The male flowers are cory mbose, oblong- 
