656 



Possibly associated with these chromatin masses in a causal 

 relation, in part at least, are the various sized vacuoles (cf. Gil- 

 christ '96, p. 316) in the cytoplasm for it is well known that chro- 

 matin bodies are frequently found during maturation and early segmen- 

 tation enclosed in the cytoplasm in vacuoles (Lillie '02, p. 482 ; Har- 

 GiTT '04, p. 461). The many examples of mitotically dividing cells 

 and especially atypical cells is characteristic of tumors. No evidence 

 of amitotic division was noted. 



A comparison of the cells of the normal adrenal of the frog with 

 those in the tumor showed that they were of the same lenght but 

 somewhat wider and had more definite cell walls but aside from these 

 two characters it was impossible to distinguish them. The lumen of 

 the normal adrenal was relatively much smaller than in the tumor. 

 The similarities of these tumor cells to the normal adrenal cells is 

 so striking that one can not long be in doubt as to their being one 

 and the same tissue. If this is the correct interpretation, then we 

 have in the frog a case of an adrenal tumor developed from the 

 entire adrenal body. 



In conformation of the suggested origin of these tumors in the 

 kidneys of the frog, we may refer to the following conclusions : Beard 

 ('03, p. 540) believes that "tumors are referable to abnormal attempts 

 at development on the part of one or more vagrant or aberrant germ 

 cells". While Ribbert ('04, p. 426) states in describing the various 

 adrenal tumors: „sie gehen tiberall aus isolierten Nebennierenteilen 

 hervor", Bashford and Murray ('04, p. 413) conclude from their 

 observations "that malignant new growths were virtually reproductive 

 tissue arising in abnormal situations and possessed of an independence 

 and power of growth like that of the testis in the MammaUan body". 



An examination of the kidney tubules in general and a minute 

 study of their individual cells in both the normal and tumorous kidney 

 failed to reveal any constant ditierences. This would seem to indi- 

 cate that, aside from a certain amount of atrophy due to the pressure 

 of the tumor, the remaining kidney tissue was not structurally modified 

 by this pathological condition. 



A comparison of these observations with the well known adrenal 

 tumors in the kidney of man shows many points of similarity. Such 

 tumors in man may or may not conceal the normal kidney tissue on 

 gross examination. Usually these adenomata are distinguished by a 

 characteristic brownish color. Delafield and Prudden ('04, p. 644) 

 distinguish papillary and alveolar adenomata and from their description 

 of these two classes it is evident that these tumors in the frog show 



