Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/347

Rh river, Mitchell Downs, may reasonably be assigned to the same age, since they contain Lingula ovalis or some other fossils in common.

In considering the most typical of this group of Australian remains, which in the whole embraces about 90 species, we have in the first place the Purisiphonia Clarkei, the forms allied to which are stated by Dr. Bowerbank not to have hitherto been found below the Lower Chalk of Flamborough Head; but as I have, of this class, lately found the genus Grantia in the Lias, though it had never before been found below the Red Crag, the presence of the former genus, though pointing to a Cretaceous horizon, does not necessarily imply it. Five of the Foraminifera, at least, are found as low down as the Lias, but they are known to pass upwards into higher formations.

Of the Brachiopoda, the Rhynchonellidoe are closely allied to Great-Oolite species. The Argyopoe have their analogues in those from the Lias; whilst the only species of Lingula is no doubt identical with the L. ovalis of the Oxford Clay and Upper Oolites.

Among the Conchifera, the Avicula braamburiensis, again, evidently connects the series with the Oxford Clay, some of the other species of that genus apparently belonging to the same natural group. The Trigonioe have their nearest alliance with those of the Portland Oolite.

Respecting the Belemnitidoe, Professor Phillips leans to the conclusion that, with the exception of the large phragmacone allied to B. paxillosus of the Lias, the others are more nearly related to Oxford-Clay types than to those of any other formation.

Under these circumstances it is not easy to decide with certainty as to the exact position of the fossils that come from Wollumbilla. The Lias, the Great Oolite, the Oxford Clay, the Portland Oolite, and the Cretaceous beds may each put in a claim; but that of the Oxford Clay appears to be the strongest. That they all belong to the Upper Oolite may with safety be inferred.

There remain the genera Panopoea, Mya, and Thracia, from Bungeworgari and the Amby river, and the gigantic Crioceras. From the nature of the matrix, though this does not pass for much, they appear to have been derived from beds of a different character from those from the other districts. As similar Criocerata have never been found below the Lower Greensand, it is reasonable to infer the presence of Neocomian beds in Australia, from whence it may have been derived.


 * Plantae (wood).
 * Purisiphonia Clarkei, Bowerbanke.
 * Cristelleria acutauricularis. Ficht. & Moll.
 * — —cultrata, var. radiata, Moore.
 * —acutauricularis, var. longicostata, Moore.
 * Dentalina communis, D'Orb.
 * Polymorphina lactea, W. & J.
 * — —gibba(?), D'Orb.
 * Planorbulina Ungeriana, D'Orb.
 * — —lobatula, D'Orb.
 * Vaginulina striata, D'Orb.
 * Pentacrinus australis, Moore.
 * Echinus (spines).
 * Serpula intestinalis, Phil.