192 ORCHIDACE. [| PacHYsTOMA. 
P. senile, Reichb. f. in Bonpl. tii, 251; F. B. I. v, 812; K & P. 
in Ann. R. Bot. Gard. Cale viii, 101, t. 140 ; Duthie id. ix, pt. 2, 
108 ; Prain Beng. Pl. 1014. 
An erect terrestrial herb, leafless when in flower. Rhizome rather 
stout, producing scapes and solitary leaves at intervals of about 2 in. 
Leaf longer than the scapes, linear, membranous, 4-5-nerved. Scapes 
about 12 in. high, clothed with many pale striate sheaths 1-2 in. long. 
Racemes many-flowered. Flowers about $ in. across, greenish-white 
tinged with pink or purple, gland-puberulous; floral bract longer 
than the curved stalked pubescent ovary, erect, lanceolate, acuminate. 
Sepals unequal ; dorsal oblong, rounded at apex ; lateral pair spreading 
oblong-lanceolate, subacute. Petals narrowly spathulate, re-curved 
puberulous as are the sepals. Lip sessile on the base of the column, 
3-lobed, broadly oblong, gibbous at the base, pubescent ; side-lobes 
acutely faleate; terminal one suborbicular, recurved and abruptly 
* acuminate at the apex; upper surface of disk with 5 stout crested 
ridges extending from base to apex. Column dilated upwards, 
puberulous. Anther on the back of the column, indistinctly 8- 
celled. . 
Dehra Dun (T. Thomson, Mackinnon) ; also in many localities within 
the area of this flora from the Jumna eastwards to Moradabad and 
N. Oudh. Flowers in Apri]. Distris.: Outer Himalayan ranges 
from Garhwal to Sikkim ; also on the Khasia Hills, and eastwards 
to the Nicobar Islands, and the Malay Archipelago to 8. China. It 
occurs also in N. Bengal and Chota Nagpur and extends southwards 
to S. India ‘and Ceylon. 
8. THUNIA, Reichb. ; included under Phatus in Fl. Brit. Ind. 
v, 816. 
Terrestrial, rarely epiphytic herbs. Stems slender or equaily 
thickened along their entire length, elongate, leafy, with many 
foliaceous sheaths below. Leaves distichous, lanceolate, glaucous. 
Flowers appearing with leaves, large, showy, in terminal drooping 
racemes; bracts large, scarious. Sepals erecto-patent, subequal, 
lanceolate, acute. Petals like the sepals. Lip adnate to the base 
of the footless column, shortly spurred ; side-lobes short, involving 
the column; mid-lobe fringed. Anther narrow, pendulous, incom- 
pletely 4-celled ; pollinia 8, waxy, attached in fours to a granular 
membrane; rostellum 3-lobed.—Species about 9, in tropical and 
temperate regions of the Old World. 
