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  ― 303 ―

CCLXXXV. E. rariflora F. M. Bailey.

In Queensland Agric. Journ., January, 1914, p. 62, with plates.

FOLLOWING is the original description:—

A tall tree not recorded as very abundant; branchlets slender of a pleasing red colour. Leaves very variable in shape, those of the flowering branchlets varying from lanceolate to oblong or even ovate, from 2–4½ inches long and ½–1 inch broad, or the ovate ones still broader on slender petioles of about 1 inch. On young trees the leaves are almost orbicular, or sometimes obversely reniform, and mostly broader than long, but always slightly decurrent on the petiole from ½–3 inches long and ½–3½ inches broad, apex sometimes emarginate, texture thin, in the young leaves, almost membranous. (The petioles in these large leaves are often over 2 inches long.) Parallel nerves numerous, slender, branching at the top, where they join the intramarginal one, which is sometimes very close, at other times rather distant from the edge, the smaller veins forming a very delicate irregular reticulation. Oil dots numerous. Inflorescence composed of slender erectopatent panicles of usually few scattered pedicellate flowers; at times in umbels of three or four flowers. Operculum very short, scarcely exceeding 1 line, blunt or very slightly umbonate. Stamens inflected in the bud, the outer ones 1½ lines long. Anthers globular, opening in broad slits. Fruit (including the short pedicel) 4 lines long, about 2 lines diameter; rim rather broad. Capsule sunk, 4-celled, the valves not exserted. Seeds small, somewhat pear-shaped, dark brown and slightly rugose.

The trunk and large branches are (according to information and specimens kindly supplied to me by Dr. T. L. Bancroft) covered with hard-fibrous, black, corrugated bark, such as would merit the name of Black Box (Rhytiphloiæ). The colour of the timber is pale brown.

Range.

It is confined to Queensland, so far as we know at present, the only specimens known coming from Eidsvold and Mundubbera.




  ― 304 ―

Affinities.

The author was struck by the remarkable shape of the juvenile leaves, but suggested no affinity.

The affinity is with E. populifolia Hook., see Plate 48, Part X. There is no doubt that the two species are closely related, and it may be that they belong to the same species. I have received admirable specimens and notes from Dr. T. L. Bancroft, who suggested hybridism, an opinion I held for a number of years, but which I abandoned.

If the references and plates to E. populifolia and E. rariflora be examined, it will be found that in both species we have a predominance of round or poplar-leaves (populifolia), but also lanceolate leaves of various widths. In E. populifolia we have the narrower leaves in trees which do not appear to carry the broadest leaves, or which have not been collected on the same tree. In E. rariflora we have the two kinds of leaf on the same tree.

These narrow leaves above referred to are shiny and are generally recognised as belonging to E. populifolia; indeed, bushmen call the shrub or tree producing them “Narrow-leaved Bimble Box.” It is around these narrow leaves that the uncertainty, referred to hybridism as one explanation, has gathered. (For example, I thought the explanation was in assuming a hybrid between E. populifolia and E. bicolor, the latter being a species often associated with the former, and having narrow leaves.)

The explanation I submit at the present time is that in all these forms we have one comprehensive species, consisting of—

  • 1. E. populifolia, with broad leaves, as we usually know it.
  • 2. With lanceolate leaves of various widths.
  • 3. E. rariflora, with leaves of (1) and (2) combined on the same tree.

I believe that we have isoblastic and heteroblastic species which are but forms of one another, and that we keep them apart because we have not the connecting evidence.

In the present case I have given the evidence as to leaves; I cannot see any difference in inflorescence and fruits. The barks and timbers appear to be alike. I have given sufficient evidence to cause both Queensland and New South Wales botanists to endeavour to settle a very interesting and far-reaching point as to the relations between, or the identity of, the two species.

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