177] _ENGELMANN—REVISION OF THE GENUS PINUS, ETC. 17 
P Halepensis,\* Pyrenaica.*® 
B. Ducts Dela RHA 
a. Cones subterminal. 
§ 6. sb rampviuer ~Mtosty America, with three Old World species. 
* Leav n fives, ducts usually free of strengthening cells. 
Pestdictvudh stant Priger and Mexico to Arizona and 
California. 
P. leiophylia,® tenuifolia, te" pig aidak ai Montezume™ ( Hart- 
wegit), Torreyana,” Arizonic 
** Leaves in threes, sometimes in fours or fives, their sheaths 
persistent; strengthening cells under the epidermis, around 
ducts, i us ually alto 1 near the oS ee bundles. — 
Eup America, Mexico, and Canary 
Islande. 
r. pene ponderosa? (Feffreyi), Canariensis.?* 
aves in threes, their sheaths deciduous.—Mexico and 
hsidol 
ee Oe Tie 
*** TLeaves in twos, generally with some gear’ cll 
around ducts. Laricfones.—Europe to Asia an ca. 
P. Laricio?® (Austriaca), Thunbergii,*® contorta®’ cturayana) 
&. Cones lateral. 
§ 7. Tap#.—Mostly American, only one Old World species. 
* Leaves in threes, ducts tle without strengthening cells. 
Eutede.—North America to Mexico. 
P. Sabiniana,?* Coulteri,?* inven ak paitaict Teda,*' hen 
eomiiinndig- Greggti, Teocote, pat 
** Leaves in twos; cones with very stout prickles. Pungentes. 
+ Ducts without strengthening cells.—North America. 
P. inops (clausa**), pungens,** muricata.*® 
++ Ducts surrounded by strengthening cells. —Southern Eu- 
rope. 
P. Pinaster.*" 
*** Teaves in twos, or in the first often also in threes; cones 
with weak or deciduous prickles. M/tes. —Eastern North 
America. 
P. mitis,>*® glabra,*® Banksiana.*° 
C. Ducts roedenns 
- § 8 AusTRALES. Leaves in twos to fives; timber very heavy and 
resinous. Bis ai North America, West Indies, and one spe- 
cies in Mexico. / z 
