Gaillonia. | LXX. RUBIACEZ (HIERN). 233 
Leaves narrowly linear, rather fleshy, sessile, }-1 in. long, margins 
revolute; sheaths of the stipules very short, sete usually 2 or of the 
lower leaves obsolete, short. Flowers about 3-4 in. long, subsessile, 
solitary or few together, sheathed at the base by a pale calyx-like 
shortly 6-cleft involucre of }-} in., arranged in simple and alternately 
branched terminal spikes; teeth of the involucre ovate, subacute. 
Calyx-teeth 2, foliaceous, pule, elliptical, narrowed at both ends, 
¢ in. long; the 2 other teeth minute or obsolete. Corolla shortly 
salver-shaped, exceeding the calyx; lobes 4 rarely 5, rather small. 
Stamens 4-5, 2-3 with short filaments, the other 2 subsessile. Style as 
long as the corolla-tube, glabrous, bifid with short slender lobes. Fruit, 
including the calyx-teeth, 4 in. long.—Spermacoce calyptera, Decaisne 
in Ann. Sc. Nat., Sér. ii., i. p. 267. 
Wile Land. Soturba, Coast of Nubia, Schweinfurth ! 
Occurs also in Arabia Petrea. 
72. SPERMACOCE, Dill. ; Benth. et Hook. f. Gen. Pl. ii. p. 145. 
Calyx-tube campanulate or turbinate, often compressed ; limb usually 
of 4-2 more or less conspicuous teeth and sometimes of small interme- 
diate ones, more or less persistent. Corolla funnel-shaped or salver- 
shaped, membranous; tube short or elongated; throat naked or 
bearded at the base; lobes usually 4, rarely 3 or 2, spreading, valvate 
in the bud, often setulose at the apex. Stamens 4, rarely 3 or 2, in- 
serted at the top of the corolla-tube, usually glabrous ; filaments slender ; 
anthers oval-oblong or oblong, usually rather short, fixed at the back, 
usually exserted. Disk cushion-shaped or obsolete. Ovary 2-celled ; 
style slender, equalling the corolla-tube or exserted ; stigma subcapi- 
tate, bilobed; ovules solitary, attached to the middle of the septum, 
amphitropous. Fruit small, dicoccous, splitting down the middle from 
the apex ; cocci l-seeded, one or both dehiscing at the apex. Seeds 
oblong ; umbilicus ventral, longitudinally furrowed on the face ; testa 
shining ; albumen hard; radicle inferior—Herbs usually annual, 
occasionally undershrubs, with opposite sessile or subsessile leaves, 
shortly sheathing stipules adnate to the base of the leaves truncate and 
tipped with sete, and usually small densely verticillate or capitate her- 
maphrodite flowers in terminal and axillary clusters. 
. A large genus, tropical and subtropical, the greater number of the species found 
in America, 
Leaves at the base of the flower-heads spreading or rarely 
reflexed. Annual herbs. 
racteoles not numerous nor conspicuous, or plant very 
slender. 
Calyx-teeth all small, obscure (or sometimes 2-1 pro- 
longed, subulate) . . . 1. 1 ee ee et 
Calyx-teeth 4, subequal, not yery small. 
Corolla-tube exceeding the calyx-teeth. 
1. S. tenuissima. 
More or less hirsute, very slender . 2. 8. filiformis. 
Hispid-hirsute, not very slender 8. S. Phyteuma. 
Glabrous, not very slender 4. S. compressa. 
