OF INDIA AND CBYDON. 
217 
Thallus various, usually freely floating from attached base 
exogenously branched, with marginal ultimately 1-flowered 
secondary shoots. Flowers enclosed in spathes, splitting 
irregularly at the tip, and subtended by 2-8 (usually 4) 
fleshy scaly bracts. 
Flower zygomorphic, naked, enclosed before anthesis in a tabular, 
usually oblanceolate spathe, which opens irregularly at the tip, pedicel- 
late, the pedicel lengthening as the fruit ripens and shedding its 
deciduous cortex. Stamens 2, rarely 1, monadelphous, with a 
filamentous staminode on either side of the common stalk. Pollen 
didymous. Ovary symmetrical, elliptical, 2-locular, with two equal or 
unequal subulate marcescent stigmas with small papillae. Ovules oo. 
Capsule isolobous, 8- or rarely 9-12-ribbed, the ribs on both valves 
decurrent into the pedicel, septifragal, both valves persistent. Seeds oo . 
Submerged herbs with the habit of Fucus and other seaweeds. 
Primary axis (? always) very short, non-flowering, giving rise laterally 
by endogenous development to a thallus of phylogenetic root nature, 
exogenously branched with root cap, ribbon-like, cup-like, filamentous, 
f ucoid, often crisped or twisted, attached to the rock by a foot or by 
haptera, or by a creeping basal portion, or at all or most points, but 
usually with the distal parts drifting freely out in the water. Secondary 
axes CO , endogenous on the upper sides of the thallus near the edge, or 
rarely in the central parts, consisting in the vegetative season each of a 
fascicle of small leaves with included evanescent axis, and all or some 
of them ultimately floriferous. Vascular bundles leading to floriferous 
shoots, and immediately adjacent parts of tissue of thallus becoming 
woody in flowering season, the rest of the tissue and the non-flori- 
ferous parts ultimately falling away (as, e.g., in most herbarium 
specimens). Floriferous axes exserted, with 2-8 (usually about 4) 
distichous imbricated bracts, the upper larger, narrowly linear to broadly 
ovate or helmet-shaped, sheathing, thicker on the upper side, formed 
by the enlargement of the sheathing bases of the leaves and the fall or 
decay of the tips. Flower solitary, terminal, enclosed in spathe, opening 
when exposed to air. 
The Indian and Ceylon species here included form a very 
natural group. There are also two species in Madagascar, 
about which more information is required. I use the genus 
in practically the same sense as defined by Tulasne. The 
latter’s section Ceratolacis was made into an independent 
genus by Weddell, as mentioned above, but on further exami- 
nation may probably be found to be best placed in Dicræa. 
Tulasne’s other sections are based on insufficient knov/ledge 
