TRIASSIC PERIOD 
Other molluskan life spreads through the seas 
Pearl-oyster, Cockle, Scallop families. 
Types old and new of Sea-snail plod their way, 
And some whose forms will live on till to-day. 
Old Cambrian forms of Nautiloids are here, 100 
But dwindling now, and soon to disappear. 
Whilst forms more close to Cuttle-fish allied, 
With horny hooks and bags of ink supplied, 
Are now abroad : the race of Belemites 
Gregarious living, camped on muddy sites. 105 
The Goniatites that in the Age before 
Controlled the Ammonoid ranks are now no more. 
But in their place the Ceratites now rise, 
Less simply shelled, and other families 
Come too in view : Arcestes here are found no 
In hooded shells, with whorls compactly wound. 
Some Tropites too appear, in handsome shells, 
With radial ribs, enriched with tubercles. 
And other forms attest the progress won 
By Ammonoids, though Goniatites be gone. 1 1 c 
Wide spreads the race, and this is marked to be 
The happiest span in all its history. 
Descendants of the Shark-like families, 
That ranged afar in Carboniferous seas, 
Are here much as their sires. The while among 120 
The Ganoid ranks new finny tribes have sprung. 
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