Widely different are the ant-house plants, of which North Queensland has two genera. One is purely an epiphyte, growing attached to a tree like many of the orchids. In both genera the gouty stems are hollow, a feature of which ants take advantage; they are merely occupiers, not the makers of their homes. Few, if any, of the plants are uninhabited by a resentful swarm, ready to attack whomsoever may presume to interfere with it. It is discomposing to the uninitiated to find the curious “orchid,” laboriously wrenched from a tree, overflowing with stinging and pungent ants, nor is he likely to reflect that the association between the plant and the insect may be more than accidental.
Some of the commonest wattles exhibit singularity of foliage well worth notice. Upon the germination of the seeds the primary leaves are pinnate. After a brief period this pretty foliage is succeeded by a boomerang-shaped growth, which prevails during life. Botanists do not speak of such trees as possessing leaves, but “leaf-stalks dilated into the form of a blade and usually with vertical edges, as in Australian acacias.” If one of these wattles is burnt to the ground, but yet retains sufficient life to enable it to shoot from the charred stem, the new growth will be of pinnate leaves, shortly to be abandoned for the substitutes, which are of a form which checks transpiration and fits the plant to survive in specially dry localities. Several of the species thus equipped to withstand drought are extremely robust in districts where the rainfall is prolific. There are no data available to support the theory that such species in a wet district are more vigorous and attain larger dimensions than representatives in drier and hotter localities. In her distribution of the Australian national flower, Nature seems to be “careless of the type,” or rather regardless in respect of conditions of climate.
Human beings, and occasionally animals lower in the scale, deviate distressingly in their conduct from the general. Plants, too, though lacking the organ of brain, are subject to aberrations of foliage almost as fantastical as the mental bent which in man is displayed by the sticking of straws in the hair. “Phyllomania” is the recognised term for this waywardness. One of the trees of this locality, the raroo (CAREYA AUSTRALIS), seems singularly prone to the infirmity, for without apparent cause it abandons habitual ways and clothes its trunk and branches with huge rosettes of small, slight, and ineffective leaves, evidence, probably, of vital degeneration.
Among the beautiful trees of this Island there is one, PITHECOLOBIUM PRUINOSUM, possessing features of attraction during successive phases of growth. The young branches, foliage, and inflorescence, are coated with minute silky hair, as if dusted with bronze of golden tint. The dense, light, semi-drooping foliage produces a cloud-like effect, to which the great masses of buff flowers add a delightful fleeciness, while the ripe pods, much twisted and involved (to carry similitude as far as it may), might be likened to dull lightning in thunderous vapour. The tree flourishes in almost pure sand within a few yards of salt water, and, being hardy and of clean habit, might well be used decoratively.
Standing with its feet awash at high tide, the huge fig-tree began life as a parasite, the seed planted by a beak-cleaning bird in a crevice of the bark of its forerunner. In time the host disappeared, embraced and absorbed. Now the tree is a sturdy host. Another fig envelops some of its branches, two umbrella-trees cling stubbornly to its sides, a pandanus palm grows comfortably at the base of a limb, tons of staghorn, bird's-nest, polypodium, and other epiphytal ferns, have licence to flourish, orchids hang decoratively, and several shrubs spring aspiringly among its roots. But the big tree still asserts its individuality. It is the host, the others merely dependents or tenants. Most of the functions of the tree are associated with the sea. Twice a year it studs its branches with pink fruit, food for many weeks for a carnival of birds, the relics of the feast dully carpeting the sand. Before the first fruiting the old leaves fall, and for a brief interval the shadows of branches and twigs, intricate, involved, erratic, might be likened to unschooled scribblings, with here a flourish and there a blot and many a boisterous smudge. Soon—it is merely a question of days—the swelling buds displace millions of leaf-sheaves, pale green and fragile, which fall and, curling in on themselves, redden, and again the yellow sand is littered, while overhead fresh foliage, changing rapidly from golden, glistening brown to rich dark green, makes one compact blotch. And when the wind torments sea and forest, and branches bend and sway, and creepers drift before it, the white blooms of the orchids, so light and delicate that a sigh agitates them, might be “foam flakes torn from the fringe of spray” and tossed aloft.
The technical description of a fairly common tree—IXORA TIMORENSIS—is silent on a quality that appeals to the unversed admirer almost as strongly as the handsome flowers, which occur in large, loose panicles at the terminals of the branches. Boldly exposed, the white flowers as they lose primal freshness change to cream, but last for several weeks. The omitted compliment from formal records is the singular fragrance of the flowers—strong, sweet, and enticing, though with a drug-like savour, as if rather an artificial addition than a provision of Nature. During December the perfume hangs heavily about the trees, being specially virile in the cool of evening and morning. Being confined to the tropical coast, away from the centres of population, and flowering at a season when visitors avoid the north, the scented Ixora has so far remained uncommended. Those who are familiar with it in its native scene dwell on its unique excellence, and are proud to reflect that when a comprehensive catalogue of the flowering and perfumed plants of Australia comes to be compiled it will stand high in order of merit, being unique and characteristic of the richness of that part of the continent in which it exists naturally.
Twice during lengthy intervals have I been perturbed by the conduct of the sea-swallows (terns) which breed in this neighbourhood. They select for their nurseries coral banks, depositing large numbers of eggs beyond the limit of high tides. In obedience to some law, the joyful white birds began to lay in September, five or six weeks earlier than usual. It seemed to be a half-hearted effort to maintain the strength of the colony, the unanimous and general purpose being postponed for three months, when numerous clutches and marvellously variegated eggs embellished the coral. But that which was a perfectly safe and wise undertaking in September was a foolish and dangerous experiment in December. The tides then approach their maximum, flooding areas denied three months previously. Wholesale tragedy was inevitable. The full moon brought bereavement to many parents, for the sea overwhelmed the nurseries, or the best part of them. Many wise birds had laid their eggs above the limit of the highest tide. Others screamed in protest against the cruelty of the sea, for eggs and fluffy chicks do not surely represent legitimate tribute to Neptune. Several fledglings were found half buried in sand and coral chips, some with merely the head with bright and apprehensive eyes obtruding. Why were not the whole of the parents of the colony prudent when in default the penalty was inevitable? Five score were wise, five hundred were foolish, and the natural increase from the second brood must have been seriously diminished. Several of the parent birds had brooded over their eggs until overwhelmed by the surges and drowned. Some on the tide limit squatted buried to the eyes in sand and seaweed. Of one the tip of a wing only protruded. It was alive, fostering unbroken eggs.
The metallic starlings have again built on a favourite tree—not massive and tough, but a slim though tall Moreton Bay ash, the branchlets of which are not notoriously brittle. They withstand a certain weight, beyond which they snap. Why do these otherwise highly intelligent birds so overstrain branches with groups of nests that “regrettable incidents” cannot be averted? First there came to the ground a group of four, and then twenty nests, all containing eggs or helpless young. By these and similar mishaps during the season the colony suffered loss to the extent of at least a hundred.
“But, like the martlet,
Builds in the weather on the outward wall
Even in the force and road of casualty.”
How often, too, do we find nests in places absurdly wrong? Wonderfully and skilfully constructed nests are attached to supports obviously weak, and eggs are laid on the ground right in the track of man and less considerate animals. Some birds seem to lay eggs and rear young solely that snakes may not lack and suffer hunger, while how large a proportion of beautiful and innocent creatures are destined to become prey to hawks?