88 ANNALS OF THE ROYAL BOTANIC GARDEN, CALCUTTA. 
Sheathed stem 2:5—3 cm. in diameter. Leaf-sheaths furnished 
with 5—6 galleries or pairs of complete collars, : 
68. D. mirabilis. 
Stem more slender than in the type and leafsheaths with only 
one pair of complete collars. 
D. mirabilis var. oligocyolis. 
** Leaf-sheaths furnished with unequal pairs of collars. 
T Leaf-sheaths furnished with pairs of collars of which one 
: points upwards and the other downwards, but the lower 
one much smaller than the upper. 
Shesthed stem about 2 cm. in diameter. — Leaf-sheaths 
furnished with several pairs of unequal collars. Leaflets 
with 3 slightly spinulous nerves on the upper surface, 
smooth beneath. 
69. D. pseudo-mirabilis. 
Sheathed stem about 12 mm, in diameter,  Leaf-sheaths 
with 1—2 pairs of collars, Leaflets sparingly spinulous 
on 3 nerves on the upper surface and bristly spinulous. 
- 
on 5 nerves beneath. 
70. D. Forbesii. 
TT Leaf-sheaths furnished with reversed collars only. 
§ Leaflets approximate into a few groups, 3-costulate, 
Leaflets approximate in 4 groups of about 8 each, with 
3 nerves on the upper surface and the mid-costa 
beneath bristly, ^ Leaf-sheaths bristly spinulous at the 
mouth 
/1. D. Sabut. 
Leaflets 10—12 on the whole, approximate into 2-3. 
groups, bristly on the mid-costa on the upper surface, 
smooth beneath. Leaf-sheaths smooth at the mouth. 
6c ' 72. D. oligophyllus. 
Leaflets about 40 on the whole, approximate into 5-6 
groups, quite smooth on both surfaces or with the 
mid-costa alone slightly spinulous on the upper surface. 
The base of the petiole armed with very long (as 
much as £—9 cm.) needle-like spines. 
73. D. collariferus. 
