1912.] 



Examining Normal and Diseased Tissues. 



155 



the nucleus accepts the nuclear stain and shows no signs of degeneration. 

 Naturally, in the end, the cell succumbs. But, after death, even fat dis- 

 appears from its necrosed body, whose shape still remains visible as a ghost 

 in the tubercles undergoing necrosis. 



We have thus established a fundamental difference in the distribution of 

 bovine and avian tuberculosis, when jnjected into the peritoneal cavity of the 

 mouse. In the bovine variety, metastasis occurs along the blood stream 

 through the thrombosed portal veins ; in the avian variety the dissemination 

 is effected by the lymphatics. 



What prospects these experiments on the intra-vitam staining of tubercles 

 hold out to chemo-therapy hardly need be mentioned, since we now know 

 that the germ-bearing cell is selectively affected by the vital stain. 



(d) Toxic degeneration of the liver was produced by various poisons, such 

 as phosphorus, cumarin, cocaine, and, above all things, by a substance first 

 prepared by Ehrlich, called icterogen. The 1 latter is an arsenic compound of 

 Ehrlich's 606 series. On injection of a centigramme of a 1/5000 solution 

 the mouse develops severe jaundice, followed by miliary bland necrosis of 

 liver cells. Similar to cumarin, icterogen induces thrombosis in the smaller 

 interlobular portal vessels, which explains the consecutive necrosis of liver 

 cells. I have included these experiments in this paper merely to show that, 

 wherever non-inflammatory necrosis in the liver occurs, its organisation is 

 attempted by vitally stained pyrrhol cells, which leave the peritoneal cavity, 

 migrate along the liver lymphatics towards the seat of trouble, and 

 eventually assist in the repair of the damage. 



(e) Malignant Growths. — In no case, to my knowledge, does the aggregation 

 of blue-stained pyrrhol cells assume such extraordinary dimensions as in the 

 instance of malignant growths placed under the skin. They swarm around 

 the growing tumour and penetrate it along the endless blood channels which 

 furrow its lobules. In the interior of the growth most of these cells succumb. 

 I am still engaged in an inquiry into the relations existing between the 

 growing tumours and these cells. Not wishing to forsake the sure ground 

 of established facts, I merely state that the appearance of these blue-stained 

 cells on the field of tumour grafts may be regarded as a specific local reaction 

 induced by the tumour cell. When exempt from inflammatory agents, the 

 tumour attracts no other migratory cell, but only the blue-stained pyrrhol 

 cell. I am inclined to believe that these cells are the bearers of nutritive 

 material for the growth. My new chemo-therapeutic experiments on mouse 

 tumours by means of agents which damage the liver, such as icterogen and 

 " J od-phenyl arsensaures Natrium," have brought to light another important 

 fact in connection with pyrrhol cells. They absorb the degeneration 



