A Case of Hermaphroditism in the Mouse *

In a recent article Hooker and Strong described a hermaphrodite mouse which was a member of the C57 black strain. They also reviewed the cases of hermaphroditism in rodents which have been recorded in the literature.8 An additional case occurred recently in our laboratory in a mouse of the dilute brown strain. This animal was a descendant of a line in which sexual abnormalities have occurred previously; these have been reported.5 At weaning age this mouse was considered to be a normal male and was placed in a breeding pen with his four female sibs. As none of the females became pregnant, the male was kcilled and carefully autopsied at the age of 8 months. The external genitalia did not show any abnormalities. Both gonads were found undescended in the abdominal cavity. The right gonad was rather large, bean-shaped, and was connected to a smoothwalled tube which had an enlarged lower part. This part was attached to the urethra. The left gonad was an abnormally small testis surrounded by the epididymis and connected to the urethra by a ductus deferens. On this side the vesicular, coagulating prostate and ampullary glands were present and were normal in appearance. On the right side these structures were absent. The region of the urethral sinus was normal, and the bulbo-urethral glands were present on both sides. Sections were cut from the different parts of the genital system and the gonads themselves were sectioned serially. Microscopic examination revealed that the right gonad was an ovotestis. The caudal and right side contained rudimentary seminiferous tubules lined i)y Sertoli cells; in a few tubules spermatogonia and primary spermatocytes were also present. Some tubules contained calcified concretions. No interstitial cells were found. The rete testis led into short efferent ducts which ended blindly. The cephalic part of the gland contained many large "luteal-like" cells,