Lomagramma J.Sm.

Rhizome of adult plant climbing tree-trunks, broad, bearing 3-5 rows of fronds on dorsal surface (except L. brassii which has 2 rows), 3 or more fronds often attached close together, such groups rather widely separated; young parts of rhizome and young fronds densely scaly; scales peltate, smaller ones always clathrate, larger ones often with a central or basal area of uniformly thin-walled cells with darker contents; vascular system as in Lomariopsis. Stipes gradually decurrent at their bases to ridges on rhizome, the pale linear aerophore on each side of a stipe decurrent also. Young plants with slender rhizome bearing only 2 longitudinal rows of fronds, creeping on rocks or on the ground; fronds widely separated, of distinctive form (bathyphylls). Fronds simply pinnate (bipinnate in L. polyphylla Brack., New Hebrides to Fiji, also recently discovered in L. cordi-pinna Holttum in Fiji) with all pinnae, apical one included, jointed to rachis; scales on fronds clathrate, smaller ones bullate at base; veins forming a uniform network of 3 or more rows of oblique areoles without included veinlets and without main veins; edges of sterile pinnae entire or crenate. Fertile fronds with pinnae narrower than sterile, covered beneath with sporangia, venation as sterile but areoles fewer; slender-stalked paraphyses present, about as long as sporangia, their apices dilated, irregular in shape, formed of 8-10 cells with thick lateral waIis as small scales on other parts of plant. Spores lacking perispore.

In all cases where young plants have been observed, they grow on wet rocky banks of small streams in high forest, at altitudes from sea level to 1500 m. Their slender rhizomes, bearing erect fronds, are wide-creeping, extending into the forest away from the stream until they meet tree-trunks, up which they climb vertically, attached by roots, to 10 m or more (Fig. 9), developing a much thicker rhizome and larger horizontal or drooping fronds. Fertile fronds are produced on the upper parts of climbing rhizomes, probably in response to drier conditions; the only occasion on which I have seen fertile fronds on L. sumatrana in Malaya was on a plant which had recently been exposed by felling of neighbouring trees. L. sinuata in New Guinea tolerates more exposed conditions than L. sumatrana and can continue to grow after par-tial Clearing of forest. Spores are probably short-lived; this may limit their dispersal range.