1906.] Observations on the Life-history of Leucocytes. 495 



From the above it will be obvious that the second series cannot be 

 regarded as any kind of confirmation of the first, for the sufficient reason that 

 they possess nothing in common and deal with entirely different phenomena. 

 For the same reason the two series do not contradict each other.] 



DESCRIPTION OF PLATE. 



(Drawn with a 2-mni. Zeiss apochromatic, 1*40 aperture, specially constructed for a 

 10-inch tube, and a 27 compens. ocular.) 



All the cells illustrated are from the bone-marrow of the guinea-pig. 



Fig. 1. — Cell showing the granules arranged more or less in strings. 

 „ 2. — The stringing of the granules is more marked, and some of them are joined end 



to end. 

 „ 3. — Still more of the granules are joined together, forming thick threads. 

 „ 4. — An earlier stage where granules and thread are about equal in quantity. 

 „ 5. — The thread before it has begun to break up. The nucleus is hidden. 

 „ 6. — The same stage with the nucleus showing. 

 „ 7. — An earlier stage. The nucleus here stains more faintly. 

 „ 8. — A slightly different form of thread, which is not uncommon. 

 „ 9. — A very early stage. The archoplasm is seen connected with the thread. 



Observations on the Life-history of Leucocytes. — Part III. 



By C. E. Walker, Assistant-Director, Cancer Eesearch Laboratories, 



University of Liverpool. 



(Communicated by Professor J. B. Farmer, F.R.S. Received May 15, — Read 



June 27, 1907.) 



[Plate 6.] 



The phenomena here recorded were first observed among the leucocytes of 

 Axolotl, which had collected in a mass owing to the presence of a foreign 

 body or to the infliction of a slight wound.* 



Some among the mass of leucocytes thus obtained were seen to be sending 

 out protrusions from their nuclei. Often where this occurred the action 



* The methods used for obtaining leucocytes apart from the other cells of the body 

 were adapted from those of other observers who have investigated inflammatory 

 processes. Small celluloid tubes were introduced under the skin of the animal and 

 removed after being left in the body for varying periods of time. The tubes and their 

 contents were, after removal, dropped into a suitable fixative and sections made in the 

 usual manner. Better and more uniform results were, however, obtained by fixing 

 portions of the coagulated exudation from a small scratch upon the skin of the animal. 



