- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
Sixty-eight genera of radiolarians occurring in seven different Mesozoic zones in the Kurdistan area of northern Iraq are listed, together with their total age range and the horizons at which they occur. It is shown that, of themselves, these genera are not good indicators of absolute age, but considered as assemblages and in conjunction with other evidence may be very useful. Meyenella, previously thought to be a good indicator of the Jurassic, is shown to occur just as abundantly elsewhere.