- 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
Specimens of Omphalocyclus macroporus (Lamarck) exhibiting in thin section a trilocular, bilocular or unilocular megalospheric embryonic apparatus, instead of the normal quadrilocular apparatus, have been observed in upper Maestrichtian horizons of southeastern Turkey. The various appearances of the embryonic apparatus are strictly related to the various positions of the thin sections. Distinguishing new varieties on the basis of the different embryonic apparatus views observed is regarded as erroneous.