Lumbosacral transitional vertebrae were found to vary by race. It was reported that they were present in 18% of Australian aboriginals (Mitchell), 16% of Indians (Bustami), 10% of Arabs (Bustami), 8.1% of natives of Britain (Brailsford), and 5.8% of Japanese (Toyoda). Bustami studied 340 sacra of two population groups (Arab and Indian). Of these 340 sacra, 32 or 9.4% showed evidence of unilateral sacralization and 14 or 4.1% showed bilateral sacralization. Lumbarization was no found in the 340 sacra examined. Sacralization was present to some degree in 46 specimens (13.5%). The incidence of total sacralization was 10% in Arab and was 16% in Indian population groups. Arab males had a higher incidence in all stages of sacralization while it was the Indian females that showed the higher incidence in their group.