184 DIVISIONS INDUCED IN LYMPHOCYTES 



tube of 5 cc. of "coefficient jelly," 0.5 cc. (5 units) of 

 stain and . 8 cc. of alkali solution (8 units) were added, 

 together with 3 cc. of the 100-per-cent extract, and the 

 content of the tube was made up to a total of 10 cc. 

 by 0.7 cc. of water. The jelly was boiled and a film 

 made from it in the usual way, fresh citrated blood 

 being placed on it. The object was to see whether this 

 jelly w r ould cause the rod-shaped bodies again to appear 

 in the lymphocytes, for we believed that it was the 

 extract which caused their appearance. It was neces- 

 sary, therefore, to raise the index of diffusion of the jelly 

 as high as possible short of killing the cells, in order 

 to cause maximum diffusion of the contents of the jelly 

 into the lymphocytes. The coefficient of diffusion of 

 these cells is 14, and we added one more unit of alkali 

 to the jelly in order to cause the extract to diffuse to 

 the utmost into the cells. This is the equation : 



cf=(5s + 8a + l.5x + 7h + t} - (Qc + l.Sn) = 15. 



where x is the 3 cc. of extract which is alkaline to the 

 extent of about 1 . 5 units, and contains 3 per cent 

 (3 units) of sodium citrate and 1 per cent (0.5 unit) 

 of sodium chloride. 



Several fields of the specimen were first looked at 

 and the ordinary resting condition of the lymphocytes 

 noted. The slide was then placed in the 37 C. incubator 

 for eight minutes. The same fields (containing the 

 same lymphocytes) w r ere then again examined, and 

 pictures were seen which had never been seen before, 

 for nearly every lymphocyte in the specimen was 



