272 J. J. MACKENZIE 



larger than normal cells, and may contain numerous nuclei and are desti- 

 tute of lipoclirome pigment. The majority of them are non-malignant but 

 occasional cases have shown local infiltrative growth and some are defi- 

 nitely malignant. As a rule they occur under twenty years of age, al- 

 though they have been found in later life. 



The third type of tumor of the suprarenal medulla is that which is 

 described as neuroblastoma. These are distinctly of an unripe type and 

 consist of small cells similar to the sympathogonia. They were first 

 described as lymphosarcomata or small round-celled sarcomata and they 

 are still apt to be mistaken for small round-celled sarcomata. The applica- 

 tion of special stains and careful study of their histology revealed the 

 fact that they were derived from the sympathogonia. The nuclei are 

 similar in size to those of these cells. They have comparatively little 

 protoplasm and show a special tendency to arrange in rosette-like nests. 

 These rosettes are embedded in a fibrillar material which, with special 

 stains, can be demonstrated to be neurofibrils. These tumors are all 

 malignant and apparently all of congenital origin. Herxheimer in his 

 review cites twenty-eight undoubted cases and adds a twenty-ninth. 

 Wright, who described four cases, only two of which Herxheimer places 

 on his list, considered that tumors of this class were probably much more 

 common than supposed. In twenty-eight cases cited by Herxheimer the 

 eldest was nine years; twelve of them had not reached the third month 

 at the- time of their death. Lambert lists twenty-seven cases and adds 

 another. Undoubtedly many of these tumors have been overlooked or 

 wrongly described. Ewing points out that probably most of the retro- 

 peritoneal round-celled sarcomata of infants belong in this class. 



A rare primary malignant tumor of the suprarenal medulla is the 

 melanoma. Quite a number of cases have been described; frequently both 

 glands show the tumor. Luksch(fr) has described small brownish, non- 

 malignant cortical tumors containing melanin. The origin of these tumors 

 is obscure. Tuczek made a special study of the pigment of these tumors 

 and showed that it is certainly melanin, whilst the pigment of the zona 

 reticulata is a lipochrome. He believes that such tumors, as well as 

 the rare primary melanomata of the brain, may be derived from pig- 

 inented neuroepithelium ; that is, that they originate ultimately from 

 3ctoclermal elements. McLachlan is opposed to this view and considers 

 that they must be derived from wandering chromatophore cells which have 

 been included in the developing suprarenals. 



Met a static carcinomata and sarcomata are not uncommon in the supra- 

 renals, but unless they are so extensive as to lead to extensive destruction 

 of the glands with the development of morbus Addisonii, they are not of 

 any special significance. 



The Pathology of the Suprarenals in Its Relationship to Other 

 Endocrin Glands. A number of important observations have been made 



