Girvanella, found in Cambrian, Ordovician and Silurian rocks, as well as in later deposits, appears to have played a part in the origination of oolitic rock-structure.
They are again absent up to the Sunday river in Cape Colony, where Lower Cretaceous rocks (for long considered to be of Oolitic age) of an inshore character are met with.
In Abyssinia the Ashangi traps are certainly post-Oolitic. In East Africa the fissure eruptions are considered to belong to the Cretaceous.
Of the European Jurassic (or Oolitic) mammals our knowledge is unfortunately very imperfect; and from the scarcity of their remains it is quite probable that they are merely stragglers from the region (possibly Africa) where the class was first differentiated.
The Bedford oolitic limestone quarries in Owen, Monroe, Lawrence, Washington and Crawford counties furnish one of the most valuable and widely used building stones in the United States, the value of the product in 1905 being $2,492,960, of which $2,393,475 was from Lawrence and Monroe counties and $1,550,076 from Lawrence county alone.