PLATE XIII. 
Tryplasma congregationis, Eth.JU. 
Numerous sub-parallel corail ites on weathered surface of a limestone block. On the 
right-hand side are finely displayed the tiers of fistulas, and generally the regular 
tabulae ; at the bottom of the block is an instance of double gemmation. 
Tryplasma, sp. 
Two very long corallites of an undetermined species. 
