17 



The chief point of geological interest in this section is 

 the occurrence of the marine Cainozoic beds, which form the 

 surface of much of the middle terrace towards its upper 

 limits. These beds occupy the entire width of the washout, 

 which is at this point 68 yards, and are seen to pass under the 

 alluvial banks on either side. They are apparently horizontal, 

 and form a small scarp near their upper limits (plate i.). 

 A small creek on the northern side of this area makes a series 

 of small waterfalls by flowing over ledges of the Cainozoic 

 limestone. This creek gives a section of about 16 ft. of these 

 beds, and as they crop out again at the surface, about half- 

 way between the main exposure and the river, it may be 

 estimated that the beds in question must be, at least, 20 ft. 

 in thickness. 



The beds, for the most part, are a fairly pure lime- 

 stone, but they have been considerably leached, and from this 

 cause the rock is open in texture and most of the gastropods, 

 bivalves, and some other forms, are present only by casts 

 and impressions. A thin siliceous layer proved to be excep- 

 tionally rich in its fossil contents. 



The following palaeontological determinations have been 

 made : — 



Foraminifera (seen only in section by fracture) : — 

 Miliolina, sp. ; Nodosaria, sp. 



Actinozoa: — Cast of an Aporose coral. 



Echinodermata: — Lovenia forbesi, Duncan; Mono- 

 stychia australis, Laube ; Fibularia gregata, Tate; 

 Echinolampas posterocrassus, Gregory. 



Polyzoa : — Retepora, sp. 



Brachiopoda : — Magellania pectoralis, Tate. 



Lamellibranchiata : — Pecten hochstetteri, Zittel ; Tri~ 

 gonia semiundulata, McCoy ; Pectunculus convexus, 

 Tate; Venus (Chione), sp. ; Dosinia, sp. ; Leda, sp. 

 (cast). 



Gastropoda: — Ancillaria ligata, Tate; Turritella 

 aldingce, Tate; Conus, sp. (cast); Natica, sp. (cast). 



Scaphopoda: — Dentalium, sp. (cast). 



The above list of fossils shows no peculiar features, the 

 occurrences are such as are found in the contiguous outliers 

 of the same age, at Aldinga, Adelaide, and Gawler. The 

 Echinodermata are the most abundant of the forms present. 

 Pecten hochstetteri is also very common. The siliceous band car- 

 ries numerous examples of Pectunculus, Chione, Trigonia, 



