VARIOUS HUMAN SARCOMAS 125 



celled, has not been among those I have examined carefully for 

 protozoa. Peculiar forms, such as rhabdomyoma, in which striped 

 muscle in a rudimentary form appears, and other rarer forms of 

 sarcoma, may originate in remains of embryonic tissue. It is not 

 my purpose to discuss such points in the present place, reserving 

 them to a later time. 



A form of sarcoma that contrasts sharply with the melanotic in 

 its superficial appearance is the chloroma. Interesting cases have 

 lately been published by Dr. T. H. Butler 1 and the late Dr. F. F. 

 Leighton. 2 In the former the urine had been examined, and found 

 to be loaded with albumin before the sarcomatous growth caused 

 protrusion of the orbits. After death the tumour was found to be 

 diffused widely throughout the body. Dr. Leighton made a careful 

 histological examination, and found that the chloroma masses them- 

 selves suggested an ' infiltration ' rather than a ' growth.' He farther 

 observed that the blood might be described as myelocytic, with the 

 large hyaline myelocyte predominating. 



This latter observation brings us to the question of the relation 

 of the various forms of leucocythaemia to sarcoma. This very 

 attractive subject is one which' I have not had opportunities of 

 examining ; and such questions, important and interesting though 

 they are, do not affect the results of the close objective study of 

 tumours such as those detailed above. 



I venture to repeat the above-mentioned conclusion to the effect 

 that the difference between a pure infection such as I have described 

 as resulting in the alveolar sarcoma of the breast and an infection 

 with proliferation of a special tissue, as in the periosteal sarcoma, is 

 not radical nor does it argue against the periosteal sarcoma being 

 a parasitic disease. 



1 T. H. Butler, Brit. Med.Journ., April 20, 1907. 



2 F. F. Leighton, Journal of Pathology, October, 1907. 



