12 cxxxii. BURMANNIACE.E (wright). [Gymnosiphon. 



Cymes lax. 



Outer perianth-segments 3-lobed ; inner minute . . 1. G. usambaricus , 



Outer perianth- segments entire ; inner absent . . .2. G. squamatus. 



Cymes dense, subcapitate . . . . . . , 3. (?. congestus. 



1. G. usambaricus, Engl. Bot. Jahrh. xx. 138, t. 5, Jigs. 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 G 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. Pfi. 

 Ost-Afr. C. 151. Dictyostegia usamharica, Engl, in Abhandl. Berl. 

 Akad. Wiss.'1894, 45 (nomen). 



XMCozaznb. Sist. German East Africa : Usambara, Hoist, 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, 1 J 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, lfi7 ! 168! 



3. G. congestus, Wright. Stem slender, simple, about 2 J 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 ! 



X>ictyosteg°ia longistyla, Benth. in Hook. Niger Flora, 528, coliecteri on the 

 River Nun by Vogel and Mann, closely resembles Gymnosiphon, hut in the absence of 

 perfect flowers must remain doubtful. 



Order CXXXIII. ORCHIDEiE, (By R. 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) difi'erent ; 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 diflferent, entire or variously lobed, the 



