Bussiere describes a triple bladder, and Scibelli of Naples mentions an instance in a subject who died at fifty-seven with symptoms of retention of urine.

In the illustration, B represents the normal bladder, A and C the supplementary bladders, with D and E their respective points of entrance into B.As will be noticed, the ureters terminate in the supplementary bladders.

Fantoni and Malgetti cite instances of quintuple bladders.
The Ephemerides speaks of a case of coalition of the bladder with the os pubis and another case of coalition with the omentum.

Prochaska mentions vesical fusion with the uterus, and we have already described union with the rectum and intestine.
Exstrophy of the bladder is not rare, and is often associated with hypospadias, epispadias, and other malformations of the genitourinary tract.

It consists of a deficiency of the abdominal wall in the hypogastric region, in which is seen the denuded bladder.