12 CXXXII. BURMANNIACEX (WRIGHT). [Gymnosiphon. 
Cymes lax, 
Outer perianth-segments 3-lobed ; inner minute 5 . 1. G. usambaricus. 
Outer perianth-segments entire ; inner absent . : . 2. G. squamatus. 
Cymes dense, subcapitate . : c i S : . 3. G. congestus. 
1. G. usambaricus, Engl. Bot. Jahrb. xx. 138, t. 5, figs. A.—L. 
Stem decumbent at the base, slender, 6 in. high. Leaves scale-like, 
narrower than the stem, the lower lanceolate, the upper oblong, rather 
obtuse. Cyme terminal, bifid, 5-9-flowered ; lateral branches longer 
than the first flower. Perianth-tube cylindrical, with 6 glands on the 
outside near the top of the ovary; outer lobes 3, rather shorter than 
the tube, 3-lobed, induplicato-valvate; inner lobes 3, minute, ovate’ 
Anthers subsessile on the perianth-tube opposite the inner lobes, with 
4 globose cells. Ovary 1-celled, with 3 bilobed, many-ovuled placentas ; 
style as long as the perianth-tube; stigma large, 3-lobed—Engl. Pf. 
Ost-Afr. C. 151. Dictyostegia usambarica, Engl. in Abhandl. Berl. 
Akad. Wiss. 1894, 45 (nomen). 
Mozamb. Dist. German East Africa: Usambara, Holst, 2478. 
2. G. squamatus, Wright. A very slender herb, 2—4 in. high. 
Leaves very few, reduced to ovate scales rather broader than the stem. 
Cyme terminal, bifid. Perianth-tube cylindrical, 14 lin. long ; limb 
with 3 entire ovate lobes; inner lobes none. Anthers 3, subsessile on 
the throat of the perianth. Ovary 1-celled, with 3 many-ovuled parietal 
placentas ; style as long as the perianth-tube ; stigma 3-lobed. 
Upper Guinea. Cameroons: Efulen, Bates, 311! 
Lower Guinea. Gaboon: Sibange Farm, Soyaux, 167! 168! 
3. G. congestus, Wright. Stem slender, simple, about 24 in. high. 
Scale-leaves few, ovate, acuminate.. Cyme congested, subcapitate, about 
7-flowered. Perianth-lobes 3, oblong, acute; inner lobes none. Stamens 
3, alternate with the perianth-lobes; anthers with 4 globose cells; con- 
nective without appendage. Ovary 1-celled, with 3 parietal placentas. 
Upper Guinea. Niger Territory: River Nun, Mann, 515 partly! Cameroons: 
Efulen, Bates, 370! 
Dictyostegia longistyla, Benth. in Hook. Niger Flora, 528, coliected on the 
River Nun by Vogel and Mann, closely resembles Gymanosiphon, but in the absence of 
perfect flowers must remain doubtful. 
Order CXXXII. ORCHIDEA. (By D. A. Rolfe.) 
Perianth superior, irregular, of six free or variously combined seg- 
ments. Sepals equal, or the dorsal one (ventral if the flower is not re- 
versed) different; the lateral ones sometimes united with each other or 
with the foot of the column, forming a sac- or spur-shaped base, called 
the mentum. Petals usually free, the lateral ones often more or less 
different from the sepals, the ventral one (dorsal if the flower is not 
reversed) called the lip, very different, entire or variously lobed, the 
