The most conspicuous fossil is a coral, which appears to belong to the family of Cyathophyllidae.  The genus is perhaps new; but this the want of specimens with which to compare it, does not allow me the means of verifying.  It may, however, be classed provisionally as Cyathophyllum, to which in many respects it bears a great resemblance; and although it is somewhat contrary to the present rules of classification to assign a specific name from a person, yet, in order to do honour to my friend on account of his skill, diligence, and zeal as a naturalist, as well as a traveller, and as this is the first fossil coral brought away by the first explorer of the region in which its habitat is found, I venture to name it C. Leichhardti.

The description may be given as follows: 

Cells concavely cylindrical, not dichotomous (thus distinguished from
Caryophyllia), grouped but separate, laterally if at all proliferous.

Corallum beautifully stellular, formed by 30-35 slightly spirally-curving or regular radiating lamellae, which meet in a central point or overlap on a latitudinal axial line, and are divided by rectangular or outwardly convex and upwardly oblique dissepiments, which become, occasionally, indistinct or obsolete near the centre, thus not assuming the usual characteristic of Cyathophyllum, but rather one of Strombodes.

Surface longitudinally striated, the cellular structure being hidden in calcareous spar; the striae formed by the coalescing lamellae, which, at the extremities, seem to be occasionally denticulated, owing to the matrix interrupting their passage to the edge.  This resembles what takes place in some Astraeidae.

The interior has more the features of Acervularia than Cyathophyllum; but there are patches of broken transverse septa in the rock which exhibit the features of the latter.

Associated with this is a branching coral, a fragment of which, in a small angle of one of the surfaces of the stone, exhibits the characters of Favosites.  There are also traces of casts of Spirifers, one of which is near to S. Pisum of the Wenlock rocks. (Silur.  Syst. pl. xiii. f. 9).

The description here given is deduced from the natural appearances under the lens, and not from artificial or regular sections.  But the specimen admits of a partial substitute for this; for the surface is worn down and roughly polished, as is the case with all the exposed surfaces of ancient limestones in Australia; the result probably of the acidulous properties of rain water, or of the atmosphere, which, in a tropical climate, where violent showers alternate with great drought, is capable of producing various sensible changes in rocks in a long series of ages.  Many rocks of limestone in New South Wales, even harder than the Burdekin marble, are actually grooved in short parallel furrows, over wide surfaces, and along their sides, by some similar agency.]

CHAPTER VIII