Carcinoma of the renal cortex presents a complex pathologic problem, so complex that since Grawitz,1 in 1884, gave the first accurate description of the condition and called attention to the relation of the structure of renal carcinoma to that of the suprarenal gland, observers have constantly been attempting to name the entire group by some embryologic, histologic or other descriptive term. Birch-Hirschfield termed the tumor described by Grawitz "hypernephroma." Adami,2 on a basis of embryologic development, suggested the term "mesothelioma." Sudeck3 took exception to associating the tumor described by Grawitz with suprarenal rests, favoring their association with renal adenoma. Stoerk4 supported Sudeck's views and advanced the hypothesis that hypernephroma might arise from proliferations of the adult secreting epithelium of the convoluted tubules. Wilson and Willis5 concluded that there was almost no evidence, embryologic or histologic, in support of Grawitz' hypothesis that so-called hypernephromas have their origin in suprarenal rests, feeling