ECHINOCACTUS GRUSONII, POPULARLY KNOWS AS THE GOLDN BARRE CACTUS, GOLDEN BALL OR MOTHER IN LAW'S CUSHION, IS A WELL KNOWN SPECIES OF CACTUS, AND IS ENDEMIC TO EAST-CENTRAL MEXICO. IT IS RARE AND ENDANGERED IN THE WILD, WHERE IT IS FOUND NEAR MESA DE LEO NIN THE STATE OF QUERETARO, AND IN THE STATE OF HILDALGO. THE CACTUS GROWS IN VOLCANIC ROCK ON SLOPES AT ALTITUDES AROUND 4600 FT.
