Bill U. S. B. F. 191 2. 



Plate CIII. 



p,,; ii,s— Section thruuuli Umi'Jr uf two-vear old brook trout treated with bichloride of mercury added by continuous 

 flow to the water in proportion of l:5.uu0,0iiu. Result at the end of 11 days. Great reduction in size of tumor. Reversion 

 of tumor tis>iue to the normal type. Fish 1144. table xil. X86. 



"^^•i 



fc.XM.> 



rout Visible tumor. Marked diminution in size of the tumor and marked change in 



'"". .. .... ..• .:..„t 55 ^„..= ,.,;»V, arconio trio-ride added bv COntinUOUS 



p,„ ,|,Q nompsiuii-.' l.i.ok iroiit vis be tumor. Marked aiminmion in size ui uie ii.ii.y; n..u ,..,.. „^- -..-..„- ... 



tuinor'^i^su'ewitrr'e^su.;;; ....Ird normal, as the result of treating for 22 days with arsenic tnox.de added by continuous 

 flow to the water. Note marked change in epithelium. 1-ish 2iJ36. table xl\ . x»t>. 



