653 



For fixing, Carnoy's fluid was used, the tissues being left in this 

 mixture over night and then given a thorough washing in 95 7o al- 

 cohol, I was not able to examine the tissues at once but found them 

 to be in an excellent state of preservation after several weeks had 

 elapsed. 



The normal kidneys of the frog are about 14 mm long and 4 mm 

 wide, rather flat, oval bodies lying in the posterior part of the coelome. 

 In color they are dark red, the familiar color of the kidney. On the 

 ventral surface of each there is an elongated, somewhat irregular band 

 of tissue, the adrenal, which extends nearly the entire length 

 of the kidney (Fig. 1). A cross section of the kidney shows 

 that the adrenal varies in thickness being somewhat flat on 

 the ventral surface and dipping into the kidney giving the 

 adrenal a hemispherical shape. It is to be noted that the 

 adrenal tissue occupies only a small part of the kidney. 



Fig. 1. A normal sized kidney magnified 2 )><^, showing the normal 

 adrenal. 



The investigations of Balfour ('81), Mitsukuri ('82), Vincent ('97), 

 Weldon ('84, '85) and others indicate very clearly that we are to find 

 the origin of the adrenal bodies in Reptiles, Birds and Mammals in 

 two distinct sources; the medullary substance is derived in part at 

 least from the sympathetic nervous system, while the cortical sub- 

 stance arises either from the mesothelium or from the same cells that 

 constitute the glomus of the pronephros. Similar results are at hand 

 for fishes. While I did not find that the detailed origin of the adrenals 

 had been worked out for Amphibians yet we may infer from the man- 

 ner in which this body arises in all other Craniata that it probably 

 has a similar origin in this phylum. So that it would not be very 

 surprising if we should find a case where the adrenal tissue had 

 grown down into the kidney, instead of being limited to the surface, 

 and had produced a pathological condition. Kelly ('99, p. 283) in 

 describing tumors in man makes mention of the frequent occurrence of 

 accessory superadrenals, and further states that the cells of the adrenals 

 become misplaced jDeing found in the liver, solar plexus, epididymus etc. 

 (Cf. RlBBERT '04, p. 426). 



In the kidneys under consideration (Figs. 2, 3) it is very evident 

 that they have increased greatly in size being 21 mm long and 8 mm 

 wide which is much larger than the normal kidney. This increase in 

 size affects also the thickness as well. The color is whitish with very 

 little evidence of any brownish pigment such as is found in similar 

 tumors in the human kidney. Both kidneys have a large number of 



