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estuary wHere the deposit occiuTed, with still water, and yet 

 exposed to a feeble current that brought a light sediment from 

 no very distant land, which settled down to the bottom within its 

 quiet area. Small crystals are widely distributed throughout the 

 mass, and a few thin beds of limestone were passed through by 

 the drill, that show a dark colour, with spar veins running 

 through the mass tinged with green. The limestone is cal- 

 careous, open in texture, and highly crystalline. The Hergott 

 section rests on Primary rocks, and the last nine feet in the 

 bore is evidently a littoral deposit giving indications of a shore 

 line, containing pebbles of quartzite, rounded fragments of 

 chloritic and other schists, which tell the tale of wave action 

 on the shore as the land began to sink beneath the waters. 



The section is pretty evenly fossiliferous, but the horizon at 

 which the large bivalve casts occur, at about two hundred feet, 

 has yielded the greatest number of forms, whilst the last nine 

 feet at the base of the section have given the fewest. The 

 palaeontological features are restricted in range and belong 

 almost entirely to one group of organisms. About twenty-five 

 species of Foraminifera have been observed, and of these some- 

 thing like seventeen, or nearly three-fourths of the whole 

 number, belong to the arenaceous type. This is a very unusual 

 proportion, as the Foraminifera with calcareous and hyaline 

 tests generally far outnumber those of an arenaceous invest- 

 ment. Of the well-marked species in the list only one can be 

 considered a deep-water species ; ten have their habitat in 

 shallow water, and ten are common to both. From this 

 analysis we may safely conclude that the sea in which these 

 Foraminifera lived was of no great depth. It is not so easy to 

 determine their geological age. One and perhaps four species 

 date from Palaeozoic times, thirteen are known as Secondary 

 forms, two begin their geological history in the Tertiaries, and 

 five have not been known previously in the fossil condition. 

 The Foraminifera generally, as an order, are of little value in 

 determining geological synchronism. They yield the oldest of 

 all known existing species, and are at one and the same time 

 the most variable and the most persistent of zoological types. 

 The palseontological evidence outside of the Ehizopodal fauna 

 is equally indeterminate of the age of these beds. The large 

 bivalves, so far as I have seen them, are mere casts with a 

 chalky coating, and the two genera that are capable of 

 determination, viz., Lingula and Dentalium, are both common 

 geological genera dating from early Palaeozoic times. The 

 example obtained of the former was microscopic, and of the 

 latter broken into small fragments so as to preclude specific 

 identification. The beds in question have been variously 

 referred to the Jurassic and the Cretaceous periods. They are 



