Geological Specimens from Tasmania. 431 
sometimes assumes the form of the madrepore and fungus 
and other shapes. 
No. 25, On elevated land below the tier, St. Paul’s Plains. 
This is ¢énstone, or the oxide of tin, and a very fine spe- 
cimen, and is evidently in a clay slate of the primitive 
mountains, and the same as in Cornwall, being the killas of 
the miner. The principal part of the numerous copper and 
tin mines of that county are in these strata. 
No. 26, Fossil Shells from a bed of rock at Hunterston, 
on the Shannon River, near Bothwell. 
This is a conglomerate magnesian limestone. 'The names 
of the shells, which can just be made out, are the Productus 
gigantea and Productus antiquatus. 
No. 27, Fossil Shells from a lime quarry near New 
Norfolk. 
This specimen is mountain limestone, and the shell is of 
the family of the 7rigonotreta speciosa. 
No. 28, Fossil Shell from a quarry near Hobart Town. 
This shell is a very fine specimen of the pecten family. 
The mineral in which it is imbedded is mountain lime- 
stone, as before. 
No. 29, Specimen from the Limestone bed below the 
White Rock Tier, St. Paul’s Plains, containing large quan- 
tities of fossil shells. 
This is also mountain limestone, a formation prolific in 
shells. 
No. 80, Fossil Rock found in great abundance near Swan 
Port, East Coast. 
This is a very interesting specimen of the mountain lime- 
stone passing into chert, proving the transition of limestone 
into silex. 
The shells are not definable, as they are too much broken. 
