Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/344

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most abundant form being Planorbulina Ungeriana. These Planorbulinoe are attached in considerable numbers to the plicated surfaces of Rhynchonella and Argyope. Of Cristellaria acutauricularis there are six specimens ; whilst Polymorphina lactea, Dentalina communis (?), and Vaginulina striata have only yielded one each. As these have been obtained simply by washing the soft surfaces of several of the blocks, it is evident that the group must be abundantly represented in a fossil state on the Australian continent.

Zoophyta. — This group is not represented in the series. The supposed coral (no. 10) of Professor M'Coy's list represents the internal structure of a piece of fossil wood.

Echinodermata. — In examining the decomposed surfaces of the Wollumbilla blocks, I have detected the presence of fragments of the spines of several forms of Echinodermata ; and there are also numerous detached plates and portions of the columns of Pentacrinites.

Two blocks found on the Mitchell Downs, and recently received by me from the Rev. W. B. Clarke, show that interesting remains belonging to this class will probably be found hereafter in this district, where boulders occur, derived from a bed in great part composed of Pentacrinites.

Polyzoa. — It is not improbable that this group may be numerously represented, as there are frequent indications of Polyzoa ; but the worn condition of many of the shells to which they are attached is unfavourable to their preservation. On a cast of a Cytherea from the Maranoa river numerous reticulated impressions show that its interior was almost covered with them. Another form also occurs, with long cylindrical cells, belonging to Lepralia, which, hitherto, I believe, has not been found below the Red and Coralline Crag.

Brachiopoda. — The Queensland representatives of this group possess considerable interest from the fact that most of the species are new, and several peculiar forms are amongst them. There can be no doubt that the class is strongly represented in the deposit from which these blocks are derived; and it may be anticipated that at a future day more genera and species may be obtained from them. The only species to be recognized is the Lingula ovalis of the Kimmeridge Clay, or the L. subovalis of the Lower Greensand, which names probably refer to the same species. This shell is most abundant, as many as fifteen examples being visible on the surfaces of a block only two or three inches square. Its presence assists in uniting the faunas in several of the blocks which contain nothing else in common. Two species of Rhynchonella occur, one of them being apparently very abundant. One of these, which I have named R. rustica, approaches very closely to P. concinna of the Great Oolite and Bradford Clay. A third genus is represented by a shell (with a very finely punctated structure and closely striated exterior) to all appearance belonging to Terebratella, under which genus (in the absence of internal structure) it is placed. It is the largest of the Australian Brachiopoda ; and I have named it T. Davidsonii, after the palaeontologist who has spent a life in the elucidation of this