CV. CASUAEINACEiE 621 



the Anclamans. Largely cnltivated for the proJuction of fuel on the Coromandel 

 Coast, on the coast of North Kanara and in places inland in the Peninsula. Planted 

 in gardens and as a roadside tree in Central and Northern India, North as far as 

 Ambala. — Malay Penins. and Archip. Anstralia. Pacific islands. 



A tall, straight-stemmed tree, the ends of branches thioldy set with nnmerons long 

 slender hranchlets, which are mostly deciduous and fulfil the function of leaves. 

 Branchlets jointed, the internodes ^-J in. long, 6-8-rihbed, with fine hairs at the 

 bottom of the furrows between the ribs and stomata in the furrows only. The ribs of 

 each joint terminate upwards in the teeth of a membranous sheath, alternating with 

 the ribs of the next joint above. Opposite these teeth are axillary vegetative buds, of 

 which as a rule only one or a few grow out into branchlets. These axillary biids 

 mostly develop at the ends of branchlets, where the joints have not yet lengthened 

 out. Here the teeth of the annular sheaths are much longer (up to J in.) than on the 

 lower and older joints, and they are densely clothed with fine hairs. 



The leaftraces or vascular bundles, which enter the teeth of the sheath, giving oif 

 branches to the axillary buds, leave the central cylinder at the base of the internode 

 and run in the bark through its entire length; hence a transverse section of a 

 hranchlet shows, outside the central cylinder, a detached vascular bundle under each 

 rib and between two furrows. The wood-fibres have bordered pits, and on a transverse 

 section of the wood numerous wavy concentric bands of soft wood parenchyma are 

 conspicuous. 



PL unisexual, S monandrous, axillary under the teeth of the annular sheaths of 

 terminal short- jointed cylindric spikes 1 in. long. Periantb of 2 large scales enclosing the 

 anthers, and 2 smaller ones at right angles to the first, anthers oblong, 4-celled, filament 

 •short. 9 in small ovoid spikes at the ends of lateral branchlets, consisting of very short 

 joints, one fl. under each tooth of the annular sheath, Perianth of 2 large scales 

 enclosing the ovary, which, as the seed ripens, grow out into 2 large woody valves, 

 more or less hairy, supported before maturity by the tooth of the sheath. Ovary 1- 

 celled, with 2 pendulous ovules, only one of which develops into a seed. StjJe short, 

 dividing into 2 long filiform, garnet-coloured branches. Fr. a woody globose cone, | in. 

 diam., testa adnate to the walls of the achene, which terminates in a long membranous 

 wing, albumen 0, embryo straight, radicle superior, cotyledons fiat. The cotyledons 

 rise above the ground, followed by a pair of leaves, and afterwards by several whorls 

 of four. The tree is monoecious, <? and ? fl. are sometimes found on the same branch, 

 but (as often happens with monoecious trees) some trees habitually bear male, others 

 female fi. only. 



In Indian Timbers ed. ii. 666, Mr. Gamble justly states that the importance of the 

 Casuarina ioTTQolsiim.ing the stretches of sand on the Coromandel coast cannot be over- 

 estimated. The production of wood is rapid, 250 cub. ft. of wood (15,000 lb.) per acre 

 per annum ; moreover, other trees and shrubs come up under its shelter, and it thus 

 prepares the ground for a more varied forest growth. The wood is very hard, cracks 

 and splits, but makes excellent fuel. 



Order OVI. BETULACE^. Prantl in Engler u, 



Prantl iii. 1. 38. 



{Cupuliferce, tribes I. Betulece, II. Corylem, Gen. PL iii, 403.) 



TreeSj sometimes shrubSj moncBcious, with, few exceptions deciduons. L. 

 alternate, usually penninerved, undivided, as a rule serrate, stipules deciduous. 

 Fl. Ibuds ready formed in autumn, open early in spring, with or before the 1. 

 (J fl. in drooping catkins, anther-cells as a rule distinct. $ fl. in long or short 

 spikes, 2 or 3 fl. in the axil of one or several bracts. Each fl. consists of a 

 2-celled ovary, one pendulous ovule in each cell, and 2 long filiform styles, 

 perianth or adnate to ovary. Fi\ in dehiscent, seed one, cotyledons usually 

 oily, radicle superior, albumen 0. The cotyledons of Corylus remain under- 

 ground, those of the other genera here described are raised above ground 

 when germinating. 



Most species of Ahius, OarpiTius and Coryhis have, besides the fine med. rays, others 

 which may be called compound rays, consisting of a number of fine sometimes broader 

 rays alternating with elongated parenchymatic cells and wood-fibres. These com- 

 pound rays run through the ordinary tissue which is traversed by vessels The wood 

 fibres as a rule have bordered laits. 



