[Teratoma of the testicle with very highly differentiated structures].

A teratoma is described that was composed of differentiated derivatives of the germ layers--ectoderm (central and peripheral nervous systems, epiphysis, adenohypophysis, and skin with appendages), endoderm (bronchial and intestinal epithelia), and mesenchyme (fibrous and smooth-muscle tissue, cartilage, and bone) and of mesoderm (mesonephros).