title: Vaterite, a constituent of the eggshells of the nonparasitic cuckoos, Guira guira and Crotophagi ani.
abstract: The crystalline spherules occurring in patches on the outer surface of the eggshells of Guira guira and the bloom on the entire outer surface of those of Crotophagi ani were shown by X-ray diffraction analysis to be vaterite.
mesh_terms: D000818:Animals; D001717:Birds / Q000033:anatomy & histology*; D002119:Calcium Carbonate / Q000378:metabolism; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003461:Crystallography; D004528:Egg Shell / Q000648:ultrastructure*; D014961:X-Ray Diffraction
chemical_list: D002119:Calcium Carbonate