STANDLEY—TROPICAL AMERICAN PHANEROGAMS. 191 
valves of the fruit, in the few fruiting specimens examined, are much nar- 
rower and thinner. 
Pithecollobium macrosiphon Standl., sp. nov. 
Young branches green or gray, puberulent at first, roughened by numerous 
pale lenticels, furnished with short ascending straight spines; petioles stout, 1.5. 
to 4.8 em. long, with a low crateriform gland at the apex; pinne a single pair, 
the rachises 4 to 18 mm. long; leaflets a single pair, short-petiolate, the blades. 
obliquely elliptic, elliptic-oblong, or elliptic-oval, 8 to 7 cm. long, 1.5 to 3.8 cm. 
wide, rounded or very obtuse at the base and unequal, obtuse or very obtuse at 
the apex, mucronulate, subcoriaceous, brownish, especially beneath, glabrous, 
the venation prominent or prominulous on both surfaces ; flowers spicate, the 
spikes 5 to 6 cm. long, very dense, the bracts deltoid, minute; calyx 1 to 1.2 mm, 
long, campanulate, puberulent ; corolla 6 to 6.5 mm. long, minutely sericeous, the 
lobes oblong-ovate, acute, about half as long as the tube; stamen tube exserted 
11 to 15 mm.; valves of the fruit (a single imperfect fruit seen) 1.5 to 1.8 cm. 
wide, very thick and hard, somewhat contorted after dehiscence; seeds 1.2 to 
1.5 cm. long, compressed, dark brown, with a very large fleshy aril. 
Type in the U. S. National Herbarium, no. 252338, collected between Tumbala 
and El Salto, Chiapas, Mexico, October 29, 1895, by E. W. Nelson (no, 8398). 
Related to P. lanceolatum (Humb. & Bonpl.) Benth., and to P. calostachys, 
described above, but distinguished from both by the very short calyx. The 
stamen tube, also, is much longer than in any of the related species. 
Pithecollobium confine Standl., sp. nov. 
Densely branched shrub, 1 to 1.5 meters high, or sometimes a small tree, with 
very stout, grayish, flexuous or contorted branches, armed with numerous short 
stout straight spines; leaves clustered on short lateral spurs, the petiole 4 to 15 
mm. long, puberulent, bearing a low gland at the apex between the lowest pair 
of pinnae, the pinnae usually one but sometimes 2 pairs, the rachis, if any, very 
short, the leaflets 3 to 5 pairs, oblong-oval to rounded-oval or broadly cuneate- 
obovate, 4.5 to 10 mm. long, 2.5 to 7 mm, wide, rounded or very obtuse at the un- 
equal base, rounded to truncate at the apex, subcoriaceous, puberulent when 
young but usually soon glabrate, the venation commonly prominulous; inflores- 
cence capitate, the heads globose, the peduncles mostly solitary and axillary, 
5 to 10 mm. long, puberulent; calyx 1 to 1.2 mm. long, campanulate, puberulent ; 
corolla 2.5 mm. long, purplish, the tube glabrous, the lobes ovate, obtuse, puberu- 
lent, less than half as long as the tube; stamens numerous, the tube included ; 
fruit about 10 to 14 em, long and 2.5 to 8 em. wide, densely puberulent when 
young, black in age, the outer coat breaking into numerous irregularly angulate 
plates, the valves becoming very thick, hard, and woody, usually curved, convex, 
tardily separating; seeds usually 5 to 10, variously compressed, 10 to 18 mm. in 
greatest diameter, dark brown, smooth. 
Type in the U. S. National Herbarium, no. 638896, collected at Cape San 
Lucas, Baja California, Mexico, March 23, 1911, by J. N. Rose (no. 16339). 
The following additional specimens have been examined : 
Basa CALIFORNIA: Cape San Lucas and vicinity, Xantus 33. Los Angeles 
Bay, Palmer 548. La Paz, Palmer 86. San José del Cabo, Rose 16444. 
Catalina Island, Rose 16837. Cerralvo, Rose 16896. Agua Colorada to 
Cerro Colorado, Nelson & Goldman 7316. , 
This plant has been referred to P. flericaule (Benth.) Coult., but in that the 
inflorescence is spicate and the pinnae are usually more numerous. The latter 
species is known in Mexico only from Tamaulipas and Nuevo Leén. 
The common name is said to be “ palo fierro.” 
