298 DR A. J. WHITING ON THE 



a small daughter cell, consisting of a nucleus enveloped in a layer of hyaline substance, 

 that later becomes coloured with haemoglobin, and so an erythroblast is formed. In one 

 respect only I differ from this view, as I believe that the perinuclear protoplasm of the 

 erythroblast is, in the spleen, tinted with haemoglobin before the cell escapes. Alluding 

 to these observations, which are practically the same as Neumann made on the giant 

 cells of the liver, Bizzozero * remarks that the usual association of giant cells with 

 nucleated red blood-corpuscles, pointed out by Foa and Salvioli, affords only presumptive 

 evidence in favour of their view, and that it would have been much more convincing 

 if one had seen, what he believes none has ever seen, the protoplasm of the giant cells 

 coloured with hgemoglobin, or the nucleated red cells already coloured while attached to 

 the giant cells. Both of these phenomena we are able, as we believe, to demonstrate. 



A case of Leucocythsemia, recorded by Dr Robert MuiR,t the spleen from which I 

 examined, has a special interest with reference to blood formation. Blood taken from the 

 finger, on many occasions during life, always showed large numbers of nucleated red cells. 

 The spleen was much enlarged, but the bone-marrow and liver were unaffected. 



The Spleen contains numerous giant cells (about twenty or thirty in a section half-an- 

 inch square), very numerous erythroblasts and nucleated red blood-corpuscles, and large 

 numbers of special uninucleated vacuolated cells like those in the spleen of the child. 

 The giant cells have the ordinary characters, — coarsely granular protoplasm, a central 

 nuclear heap, vacuoles, mouth-like openings, many of which contain erythroblasts. Their 

 average measurement is probably about 40 v by 20 m. Occasionally the central nuclear 

 heap is circumscribed by a regular outline, but usually it gives off pyriform or Indian 

 club-shaped buds. (Plate III. fig. 22.) The buds vary much in size, but in the largest 

 the head of the club is as large as an erythroblast, and often it is seen to be contained 

 in what appears to be a perinuclear space. Frequently an erythroblast is seen to be 

 connected with the giant cell by the stalk of the pyriform nucleus, attached to the 

 central nuclear heap, and by a pedicle of protoplasm apparently continuous with the 

 protoplasm of the giant cell. 



The mediastinal lymph glands were greatly enlarged, but they contained no giant 

 cells, and few, if any, nucleated red cells or erythroblasts. Thus it is probable that the 

 nucleated red cells found in the blood had their origin in the spleen. 



On Artificial Ansamia in Dogs. 



The following is a precis of the experiments of Bizzozero and Salvioli,^ which prove 

 the frequent occurrence of nucleated red cells in the spleens of dogs that have been 

 rendered anaemic. 



* Bizzozero (31), p. 32. + Mum (47), p. 480 (Case 54). 



| Bizzozero and Salvioli (30), p. GOO. 



