Mohave Indian puberty and menstrual rites are correlated with genital bleeding during defloration and childbirth. Factual data include a discussion of Mohave beliefs concerning the menstrual cycle, an analysis of the purpose of and attitudes toward menstruation itself and the rites pertaining to it, a detailed description of the puberty and menstrual rites and of the girl's instruction and indoctrination during pubertal confinement. In discussing the obsolescence of these rites, it is pointed out that since, at each repetition, the rite is simplified in some respect this, in itself, provides a model for the gradual decline and obsolescing of the rite as a whole. The climacterium is also described and the