20 . ANNALS OF THE ROYAL BOTANIC GARDEN, CALCUTTA. 
pericarpal cavity; the hilum small, basal; the surface equable or nearly so (not 
pitted); chalaza apical; the raphe short; albumen homogeneous; embryo basal. 
Fruiting pertanth persistent, hardening. 
A very natural and well charaeterized genus, not having marked affinities with 
the other climbing Calamoid palms, on aecount of the peculiar structure of the spadix. 
The sterile plants however are with difficulty distinguishable from Plectocomiopsis 
and Myrialepis, having, like these, leaf-sheaths without flagella and ocreæ, gradually 
passing into the petioles, without gibbosity at the base of these, and leaflets unicostate 
with thickened margins; Myrialepis and Plectocomiopsis, however, have the lower 
surface of the leaflets dotted with minute microlepidia, which are always absent in 
Plectocomia. The long pendulous spikes, very regularly covered with approximate 
imbricate spathels protecting the small spikelets, form the most striking characteristic 
which serves to distinguish Plectocomia from all the other Lepidocaryee. 
It has been a subject of discussion if in Plectocomia the inflorescence is 
terminal or axillary. In fact the Plectocomias are all without exception monocarpic 
palms, or in other words the stem that has produced an inflorescence perishes 
after the maturity of the fruits; but the inflorescence is frequently composed of 
several partial panicles, each coming forth from the axil of a leaf, which in the 
lower panicles is very similar to the cauline ones. but becomes gradually smaller 
in the upper panicles and is finally much reduced in those of the end. 
GEOGRAPHICAL DISTRIBUTION.—The Plectocomias are exclusively N.-E. Indian and 
Indo-Malayan palms, being found in the Eastern Himalaya, Assam, Burma, Siam, 
Cochin-China, the Malay Peninsula, in continental Asia, and in the Islands of 
Singapore, Sumatra, Java, Billiton; Borneo and Mindanao. The most northerly species 
P. himalayana, which grows luxuriantly in Sikkim, has no marked affinities with 
those of the not very far distant Khasia Hills (P. khastana) and of Assam (P. 
assamica and P. bractealis); on the contrary these last three, together with P. 
Kerrana from N.-W. Siam and P. Pierreana from Cochin-China constitute a distinct 
group, havıng manifest affinities in common. Another group of allied species is 
formed by P. macrostachya of Lower Burma, P. Grifithii of the Malay Peninsula, 
and P. elongata of Java and Sumatra. 
A third group is composed of P. Muelleri’, a Bornean plant, of its ally 
P. billitonensis of Billiton, and of P. Elmeri, growing in Mindanao; this last 
having evidently a common origin with P. Mueller. 
i 
KEY TO THE SPECIES. , 
A. Calyx of the male flowers campanulate or cyathiform :. of the female flowers 
ovotd-campanulate, coriaceous, with obconical, solid and hard base. 
I. Fruiting perianth having the base obconical, but not pedicelliform in 
the fruiting stage. The calyx in the male flowers tomentose at the 
mouth. Leaflets mealy-white beneath. Fruit woolly from the fimbriate 
upturned tips of the scales. È 
