Tas. 8211. 
POLYSTACHYA LAWRENCEANA, 
East Tropical Africa. 
OrcHIDACEAE. Tribe VANDEAE. 
Ponystacuya, Hook.; Benth. et Hook.f. Gen. Plant. vol. iii. p. 540. 
Polystachya Lawrenceana, Kraenzl. in Gard. Chron. 1893, vol. xiv. p. 150; 
Rolfe in Thiselton-Dyer, Fl. Trop. Afr. vot. vii. p. 124; inter species affines 
labello roseo distincta. 
Herba epiphytica. Pseudobulbi ovoideo-oblongi, subcompressi, 2°5-4 cm. longi, 
vaginis membranaceis imbricatis tecti, 2-3-phylli. olia lineari-oblonga, 
subobtusa, recurva, 6-11 em. longa, 1°3-2 cm. lata, subcoriacea, Scapi 
terminales, 8-15 em. longi, pubescentes, 4—8-flori. Bracteae late rhomboideo- 
ovatae, abrupte acuminatae, puberulae, 6-8 cm. longae. Pedicelli puberuli, 
circa 1 em. longi. Flores speciosi, flavido-virides labello roseo, inversi. 
Sepala subpatentia, puberula ; posticum ovatum, acutum, concavum, 8 cm. 
longum, lateralia ovata, acuta, concava, 1 em. longa, Petala subconniventia, 
incurva, oblanceolato-oblonga, subobtusa, 8 em. longa. Labellum superum, 
3-lobum, 1 cm. longum ; lobi Jaterales late rotundati vel obscure angulati, 
subobtusi, breves; lobus intermedius obovato-orbicularis, apiculatus, 
carnosulus, canaliculatus, circa 7 mm. latus; discus medio callo rotundato 
obscuro instructus, basi puberulus. Columna brevissima, Jata, exalata. 
Polystachya is a large and polymorphic genus, widely 
diffused through the warmer regions of the globe, though at 
present it is not known to occur further east than Borneo 
and the Philippine Islands. Its headquarters are in Tropi- 
cal Africa, from which country 74 species were known 
when the Flora of Tropical Africa was published, and the 
number has since been increased to over one hundred. 
Very few of the species can be considered showy, and only 
three have hitherto been figured in this work, namely, 
P. grandiflora, Lindl., t. 3707, P. bracteosa, Lindl. (now con- 
sidered to be synonymous with P. affinis, Lindl.), t. 4161, 
and P. pubescens, t. 5586, the two former being from 
Tropical Africa, ‘the latter from extra-tropical South Africa. 
The one now figured is very distinct from these, and indeed 
from all others in cultivation, in its rose-pink lip, which 
renders the plant very attractive. It was discovered in the 
Upper Zambesi district by Mr. John Buchanan, who sent 
Auaust, 1908. 
