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

86 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [VOL. 35
Stamens shorter straight, the 3 abaxial longer (the straightish centric one a trifle
shorter and narrower than its incurved neighbors), all acutely sagittate at base,
at apex graduaUy or abruptiy narrowed into a porrect beak intro-antrorsely de­
hiscent by 2 pores; style subangulate, scarcely or distinctiy thickened distaUy,
incurved at apex, the stigmatic cavity infraterminal introrse; ovules 10-60; pod
linear or hnear-oblong piano-compressed (3-)7-27 cm; seeds transverse, either
1- or 2-seriate, narrowly oblong-oblanceolate in outhne, compressed parallel to
the valves, the areole sharply defined or sometimes obscure.—Amply leafy, po­
tentially arborescent shrubs and trees; stipules narrow fugacious; petiolar glands
0; hts (3-)4-13 pairs; inflorescence an exserted panicle or thyrse of subcorymbose
racemes.—Spp. 3, one pluriracial and widespread over lowland tropical S. Amer­
ica e. of the Andes, 2 narrowly endemic to e. Cuba and Hispaniola.
At least in an American context, ser. Sapindifoliae is a somewhat isolated
group. The slenderly funnel-shaped hypanthium and asymmetrically sagittate long
anthers are reminiscent of sect. Senna ser. Pictae; but the two long stamens
project, at narrow angle from each other, in a plane opposed to the vexillum, and
are not lifted sideways, as in ser. Pictae, so as to face each other in pincer
fashion. In its interior organization the flower of ser. Sapindifoliae is almost that
of ser. Basiglandulosae, but the pollen-cup of the long anthers is unappendaged
and the characteristic petiolar gland is lacking. The small ser. Galeottianae is
simUar in the infundibuliform hypanthium and loss of petiolar gland, but these
are microphyllous Mexican shrubs with obscurely beaked anthers and peculiarly
dehiscent winged pods reminiscent of some Mimoseae. The paleotropical ser.
Floridae are habitally similar to ser. Sapindifoliae, especially in their thyrsiform-
paniculate inflorescence, but the hypanthium is shortly turbinate, the sepals are
incrassate and not deflexed at anthesis, the three staminodes remain recognizably
depauperate sterUe stamens and have not dwindled as here to linear rudiments,
the fertUe anthers dehisce by one confluent pore, and the seeds are much broader
and flatter, paddle-shaped or discoid. The resemblance to ser. Floridae is perhaps
more superficial than real.
The series Sapindifoliae was perceived as such by Bentham who, however,
treated it as a subgroup ("Paniculatae Americanae," without nomenclatural intent)
of a heterogeneous sect. Chamaesenna ser. Floridae, dispersed in these
pages between sects. Chamaefistula redefined and Peiranisia. The two rare Antillean
Sapindifoliae were segregated by Britton & Rose as a genus Cowellocas­
sia, which reflected an apparent isolation among North American sennas; but no
overt acknowledgment of their relationship to the common South American S.
silvestris was made until Pittier transferred Cassia racemosa sensu Bentham (non
P. MiU) to the same genus.
Key to the Species of ser. Sapindifoliae
Plants of continental South America (Orinoco valley s.-ward); ovules 26-60.
3. S. silvestris (p. 87).
Plants of e. Cuba and Hispaniola; ovules (7-)10-18.
2. Lfts ovate-acuminate, the larger ones ± 1-2 cm wide and 2.5^ times as long; fls relatively
large, the longest sepals 6.5-8 mm, longest petals 12-17 mm; pod ± 13 cm; ovules 16-18;
mountainous n. slope of Oriente province, Cuba. 4. S. gundlachii (p. 95).
2. Lfts lance-acuminate, the larger ones 7-12 mm wide and 4-7 times as long; fls very
small, the longest sepal 4-4.5 mm, longest petal 5-6 mm; pod 3-7 cm; ovules (7-) 10-15;
coastal s.-e. Cuba (Oriente) and Hispaniola. 5. 5. domingensis (p. 96).