#stromatoolithus

Stromatoolithus is an ootaxon found in Pingling Formation, China, dating to the Maastrichtian age of the Late Cretaceous. The eggs were spherical and probably resembled that of Dictyoolithus, which is pictured above.

Sources: 

https://en.wikipedia.org/wiki/Stromatoolithus

Glut, Donald F. (2003). "Appendix: Dinosaur Tracks and Eggs".Dinosaurs: The Encyclopedia. 3rd Supplement. Jefferson, North Carolina: McFarland & Company, Inc. pp. 613–652. 

Jin, X., F. D. Jackson, D. J. Varricchio, Y. Azuma, T. He. 2010. The first Dictyoolithus egg clutches from the Lishui Basin, Zhejiang Province, China. Journal of Vertebrate Paleontology 30 (1): 188-195.