458 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
often obsolete; secondary petioles 1 to 2.5 cm. long, the apical gland small 
and sometimes obsolete; leaflets unijugate, subpetiolulate, coriaceous, obliquely 
ovate-lanceolate or elliptic-lanceolate, obtuse at the apex, semicordate at the 
base, 4 to 12.5 cm. long, 2.5 to 5.5 cm. broad, the reticulate venation conspicuous 
on both faces. 
Inflorescences spicate, single in the axils and often paniculate at the ends of 
the branchlets, the rachis 4-sulcate, puberulous, 7 to 12 cm. long, the flowers 
densely massed on the upper half; bracts often none, or represented by resi- 
dual petioles; bractlets small, hairy, scaly, deciduous; flowers large, white, 
sessile; calyx 2.5 mm. long, densely gray-pubescent, the teeth broad and irregu- 
lar; corolla 12 mm. long or over, densely grayish-sericeous, the lobes broad 
and subacute; stamen tube up to 25 mm. long, long-exserted; pistil up to 4 
cm. long, the ovary sessile, grayish, appressed-hairy, the style glabrous. 
Legume not known. 
Type from Caripe, near Cumanf, Venezuela. The description given above 
is based upon flowering specimens collected near Miraflores, Canal Zone, 
Panama, July, 1911, Pittier 8969, and at Chepo, Panama, October, 1911, Pittier 
4772, 
The original description of this species, assuming it really applies to the 
Panama plant, is very unsatisfactory. Willdenow describes the stipular spines 
as “rectae vix visibiles minutissimae,” while in fact they are large, strong, 
and always more or less recurved; and the leaflets are decidedly lanceolate 
rather than ovate-oblong. Bentham had not seen the plant when he wrote his 
first description? and it is likely that the more complete diagnosis given in his 
later memoir*® is founded on Panama specimens. Walpers and Duchassaing 
described their Panama collection of this plant as P. panamense,‘ but if Hum- 
boldt and Bonpland’s name has been properly applied by Bentham, it would 
seem that the isthmian species is identical with the Venezuelan one. Walpers 
and Duchassaing described the ovary as glabrous, but in all the specimens I 
have dissected I found it densely appressed-hairy. 
8. Pithecollobium macrostachyum (Vahl) Benth. Lond. Journ. Bot. 5: 105. 
1846. 
Mimosa macrostachys Vahl, Eclog. Amer. 3: 34. pl. 26. 1807. 
Inga macrostachya DC. Prodr. 2: 427. 1825. 
This species, collected in Cayenne by von Rohr, and described by Vahl as 
Mimosa macrostachys, does not seem to have been reported again. Bentham 
considered it at first as synonymous with P. lanceolatum, but later *® corrected 
himself as follows: 
“Since I have seen von Rohr’s specimen of the species described by Vahl, 
I am inclined to think that I have confounded two distinct plants. In the one, 
P. macrostachyum, independently of the great length of the spike, the flower 
itself is 12.5° mm. long, and the staminal tube projects 25 mm. beyond it; this 
species I have only seen from Cayenne. The other, P. lanceolatum, is indeed 
variable as to dimensions, but I never have seen the flower more than 6.8 mm., 
nor the staminal tube project more than 4 mm. beyond it; the form and size 
of the bracts are also very variable. This would include all my stations and 
synonyms except Vahl’s.” 
? Lond. Journ. Bot. 3: 198. 1844. 
* Trans. Linn. Soc. 30: 572. 1875. 
‘Walp. Repert. Bot. 2: 458. 1843. 
*Lond. Journ. Bot. 5: 105. 1846. 
*In order to facilitate comparisons, I have reduced the lines to millimeters. 
