349 



As in the case of the borings at Hergott and Mirrabuckinna 

 the Tarkaninna section, although of much greater thickness, 

 preserves a wonderful sameness of character throughout its 

 entire depth, both in its lithological character and pala^ontological 

 remains. The same similarity is observed when the respective 

 borings are compared with each other, a majority of the species 

 occurring in common over the geological area in question. The 

 respective borings have evidently passed through beds of con- 

 temporaneous age, and which must have been deposited under 

 remarkably uniform conditions. This deposit, although between 

 1,200 and 1,300 feet thick at Tarkaninna, must have had a slow 

 rate of deposition to admit of the presence of Foraminifera 

 living upon the sea bottom. On the other hand, the comparative 

 rarity of marine organisms in this formation, and the remarkable 

 preponderance of the arenaceous types of Foraminifera over 

 those with hyaline tests, seem to point to the presence of muddy 

 water, and a relativel}^ rapid accumulation of sediment on the 

 sea-floor. 



The Microzoa observed, other than Foraminifera were, a few 

 entomostraca, fragments of a small Liyigula, traces of echino- 

 derms, one or two small fish bones, vegetable tissues, and 

 cylindrical pyritous casts. 



