Cassiinae pt 1 NY-Botanical_gardens_Vol. 35_1 - Copy.pdf - Antbase

1982] CASSIINAE—SENNA 373
Pod pendulous from spreading-ascending pedicel, the stipe 5-6 mm, the hnear-
vermtform subterete or slightly laterally compressed, straight or gently incurved
body when fully fertile 10-14.5 x 0.5-0.9 cm (but often partly sterUe and ineg­
ularly strangulated or withered, the firm green valves early brunnescent or finally
blackish, the seed-locules without pulp 2-2.5 mm long, ananged in one series the
length of the cavity; seeds obhquely descending, turned broadside to the septa,
plumply obovoid 4^.5 x 2.8-3 mm, the castaneous testa smooth, highly lustrous,
exareolate.—Collections: 7.
Dry bmshy hillsides and stony riverbanks, in disturbed sites sometimes surviving
in hedgerows, 1600(s.-ward)-3000 m, scattered along the e. slope of the
Andes in lat. 17°30'-26°30'S, from the s. face of Cordillera de Cochabamba in
Bolivia s. to Sa. de Medina in n. Tucuman, Argentina.—Fl. IX-II(-V), the old
fmit sometimes contemporary with young fls.—Motucho (Cochabamba); taquillo
(Salta).
This species seems closely related to the common and widespread, often cul­
tivated S. septemtrionalis, of which it has the general habit, the relatively ample,
broadly lance- or ovate-acuminate leaflets and the showy subcorymbose racemes
of flower. It differs decisively, however, in the ventrally engraved venulation of
the leaflets and in the narrow pendulous vermhorm pod that contains only one
row of seeds.
No two collections of S. burkartiana are quite alike in pubescence, which
varies from sordid gray to yellow, from sparse to dense, and from strigulose or
minutely pilosulous to loosely pilose-tomentulose. The variation appears random,
at least in relation to dispersal, except that the longer, looser vesture is found
chiefly near the Argentine-Bolivian boundary, the sparser and shorter types to
the north and south. We have in most cases no conelation between vesture and
characters of the fmit, and it is too early to say whether there are discrete taxo­
nomic units to be defined within the species.
Fmiting specimens of what appears to be a yellow-vUlosulous form of S. burkartiana
were most unexpectedly collected in Chiriqui, Panama, in 1977 by W.
G. D'Arcy (above Bajo Chorro, 24.Ill, fr). They were taken from a cultivated
tree 5 m tall. Flowers are needed for certain identification of this interesting plant.
123. Senna vargasii (Schery) Irwin & Barneby, comb. nov. Cassia vargasii
Schery, Ann. Mo. Bot. Gard. 37: 401. 1950.—"PERU: CUZCO: Prov.
Umbamba, Machupicchu, Feb., 1938, C. Vargas C. 985.''—Holoty­
pus, MO! = NY Neg. 10620.
Doubtless shmbby but of unrecorded stature, the annotinous branchlets, fohage
and inflorescence densely pUosulous with rather coarse spreading lutescent hairs
±0.4-0.6 mm, the fohage bicolored, the ample submembranous lfts above dull
oUvaceous and only thinly pubescent, beneath especiaUy along the veins densely
so and palhd, the early racemes axillary to and shorter than lvs, later ones perhaps
forming an exserted panicle.
Stipules reflexed, thinly herbaceous, ovate ±6-7.5 x 3 mm, persistent into fuU
development of associated If, then apparently deciduous.
Lvs up to 19 cm, the stout petiole ±2-2.5 x 0.2 cm; rachis 8-10.5 cm, its
longer interfoholar segments ±2-2.5 cm; gland between proximal pair of lfts
sessUe ovoid-acuminate ±1.5 x 0.8-1 mm, and smaller glands between 2-3 suc­
ceeding pairs; lfts 5-6 pairs, strongly accrescent distaUy, the distal pair subsym­
metricaUy elliptic acuminulate ±6-7 x 2.2 cm, the shorter middle and proximal