6 Tertiary Fossils in South Australia. 



us this. Very few are calcareous (and no others can be pre- 

 served), and of those which are, the majority are so fine and 

 small, and lightly jointed, as to render their preservation 

 almost an impossibility. Thus, for instance, our Catenicellidce 

 being united by short corneous joints, their decom- 

 position and destruction is certain. The same may be said 

 of the different species of Carbasea Flustra, Bicellaria, &c, 

 &c. None of these are found in the Mount Gambier lime- 

 stone, and yet I believe we are not without some record of 

 their former existence. Under the microscope the finest dust 

 of the stone is seen to have some trace of organization, and 

 there are apparently a great many foramenifera, such as 

 Globigerina, Orbulina, Rotalia, &c, &c. Doubtless some of 

 the latter might prove to be scattered cells of Catenicella, &c. 

 I must state, in conclusion, that shells are never found 

 unless as casts, with the exception of the Fecten coarctatus, 

 and the Terebratula compta, but in other respects the forma- 

 tion is so precisely similar to the Upper Crag, Suffolk, that a 

 specimen of the latter, which I have, cannot be known from 

 Mount Gambier limestone, except by a narrow examination 

 of the fossils. Even the very concretions and texture of the 

 stone are repeated in both strata. I shall return to the sub- 

 ject again shortly. In conclusion, I append a list of the 

 fossils here figured and described : — 



EXPLANATION OF FIGUKES. 



No. 1. — Salicornaria Sinuosa, a natural size. 



No 2. — Cauda Angulata, a front and back view. 



No. &.— Cellepora Hemisphcerina, six transverse sections. 



No. 5. — Cellepora, six upper and an under surface. 



No. 6. — Cellepora tubulosa. 



No. 7. — Cellepora spongiosa, two specimens. 



No. 8.~Melicerita, an upper surface, six sections natural size. 



No. 9. — Hornera, much magnified ; a front and six back view. 



No. 10. Horner a Gambier ensis, a front, six back, and natural size. 



No. 11.— Caherea lata, a front, six back, and natural size. 



No. 12. — Crista eburnea, a magnified to natural size. 



No. 13,— Part of an axis of a coral resembling Iris Hippuris, N.B. 



These are universally disseminated through the stone. 



