53 



Marginella propinqua, two broken and worn. 

 Natica polita, one worn. 

 Marginella Wooclsii, one worn. 

 Oliva angustata, a rolled fragment. 

 Terebratiilina Davidsoni, many, but all worn. 



I am much inclined to reject those species which I have met 

 with only rarely and in a rolled condition. . . Certainly the 

 majority of the fossils obtained under the nodule band belongs to 

 the lower fauna." 



Amongst the nodules and bone remains, perfect examples of 

 some of the stronger shells belonging to the upper beds are 

 abundant, e.^., CrassateUa ohJonya, Chione suhrohorata, NatAca 

 gihhosa, PectuncuJus convexus, kc. Fragile shells are absent, 

 though they are plentiful enough in the strata above. Lower- 

 bed shells have not been noticed in the nodule band, which would 

 seem to indicate that this was laid down, not when the deposition 

 of the older beds ceased, but when that of the younger ones com- 

 menced. As said before, the beds both above and below the 

 modules are horizontal, so that there is here simply a gap in the 

 -succession of the tertiary strata. 



A much larger number of species occur in the low^er than in 

 the upper beds, especially amongst the siphonostomatous uni- 

 valves, while the brachiopoda are almost confined to them. It is 

 ^'enerally admitted that their fossils could only have lived in seas 

 warmer than those of the present coasts of Southern Australia. 

 On the other hand, the shells of the upper beds indicate a nearer 

 approach to the existing temperature of our waters. Bivalves 

 and holostomatous univalves predominate in them, and though, 

 as compared with the lower beds, the number of species is small, 

 individual examples are usually more abundant. Omitting for 

 the present the shells referred to in column 4 of the summary, 

 the total number of species recognised in the lower beds is 416, 

 and in the upper 174. Of these, 81 species in the lower, and 37 

 in the upper beds have not been fully examined. By deducting 

 them, we get 335 species belonging to the lower, and 137 to the 

 upper zone, which have received distinctive names, and which 

 may therefore be regarded as authenticated species. In the lower 

 beds five living species are known, viz. : — 



Ostrea hyotis, Linn. Saxicava arctica, Linn. 



Limopsis aurita, Brocchi Hipponyx foliaceus, Q. &: G. 



Belcheri, Ad. k R. 



The percentage of recent to extinct forms is thus only 1-5, 

 which would place the beds low down in the eocene division of 

 the tertiaries. 



