DISA. 153 
the middle tooth of the rostellum and the fold in the stigma are not 
easily detected. It is much less common than D. obtusa. 
Pratr 15.—Figs. 1, 2, flower, front and side views, x 4 diameters; 3, side 
sepal, x 4; 4, lip, x 4; 5, petal, x 6; 6, ditto, from another plant, x 6; 7, 8, 
column and petals, front and side view, magnified; 9, column, side view, mag. 
18. Disa obtusa, Lindley, Gen. & Sp. Orch. (1888), p. 3855.— 
Glabrous, erect, 5-10 in. high; stem sparingly leafy; leaves linear, 
acute, sheathing at base, erect, 14-3 in. long; spike densely many- 
flowered ; bracts ovate-acuminate, the lower longer, the upper shorter 
than the flowers; side-sepals oblong, obtuse, spreading, 2 lines long; 
odd sepal galeate, obtuse, 2 lines wide; spur obtuse, about 3 line long; 
petals oblong, knee-bent in the middle, adnate to the column at base ; 
lip linear, subacute, deflexed, 14 lines long; anther resupinate; 
rostellum erect, arms somewhat divaricate, tuberculate between the 
column and petals on either side. 
Has. In shallow, moist valleys of the mountains of the Peninsular range, in 
several places, alt. 800—2400 ft.; fl. Nov.—Dec.; Sieber; Wright; Bolus, 4549; 
Herb. Norm. Austr.-Afr., 336. 
Flowers generally whitish, with lilac spots and stripes; petals 
yellow; rostellum and stigma white; it varies to darker colours, with 
lilac ground, and purple spots and stripes. Allied to the preceding. 
The capsules in this species frequently untwist, and become straight 
after maturity, the withered flower then standing with its helmet 
facing the axis of the spike. Darwin has noticed the same untwisting 
in the ovary of Malawxis paludosa (‘ Fertilisation of Orchids,’ ed. 2, 
p. 181). This is one of the commonest of the small Disw# near Cape 
Town, and in some years is abundant. 
Puatr 34, — Fig. 1, flower x 4diam.; 2, odd sepal x 6; 3, side sepals x 6; 
4, side petals x 6; 5, lip x 6; 6, 7, column, side and front view, magnified. 
19. Disa cylindrica, Swartz, in Kongl. Vetensk. Acad. Handl., 
vol. xxi. (1800), p. 213.— Erect, glabrous, 5-12 in. high; scape laxly 
leafy ; leaves lanceolate, acute, waved, erect or ascending, sheathing 
at base, 2-3 in. long; spike cylindrical, densely or loosely many- 
flowered, usually about one-third of the length of the scape; bracts 
lanceolate, acute, leaf-like, about the length of the flowers, or longer 
or shorter; side-sepals obliquely oblong, acute, apiculate, 3-nerved, 
recurved, or erectly spreading, 3-4 lines long; odd sepal cucullate, 
acute or obtuse, with a dorsal point near the apex, shortly saccate at 
base, the sac mostly about a line long and as thick, the whole as long 
as the side sepals, and adnate to them shortly above the base; petals 
erect, obliquely lanceolate, subacute, cordate on the anterior margin, 
fleshy, adnate to the column at base; lip linear, obtuse, thick and 
fleshy, about 2 lines long; rostellum subovate, erect, without arms, 
