The testicles are placed in the scrotum behind the penis. On entering puberty, the penis, scrotum and testicles will enlarge toward maturity. In boys, puberty begins with the enlargement of the testicles and scrotum. Having the scrotum and testicles situated outside the abdominal cavity may provide additional advantages. The labia majora are homologous to the male scrotum. The testicle may be higher than usual in the scrotum and vomiting may occur. He had bifid scrotum, one testicle on each side of the scrotum. The male genitalia are the penis and the scrotum. It is located behind the perineum which is located behind the vagina or scrotum. A newborn's genitals are enlarged and reddened, with male infants having an unusually large scrotum. They may also be discovered by self-inspection of the scrotum and testicles. Males have a blue scrotum and red penis. The male has a red penis with a black scrotum. In one study researchers sampled subjects' urethra, scrotum and penis. DHT "in utero" causes differentiation of penis, scrotum and prostate.