308 DR A. J. WHITING ON THE 



number of leucocytes, there being one uninucleated to three multinucleated. About 

 ten nucleated red cells were found in each film. 



On the 2ith day three or four large cells were found in four preparations. One cell 

 was seen under the microscope on the warm stage about two minutes after it was 

 removed from the body ; in it a coarsely granular core of protoplasm was surrounded by 

 a rim of yellowish finely granular almost hyaline protoplasm, that showed active amoeboid 

 movement. In the rim were several rounded projections, four of which were seen to 

 become detached as small round cells. Nucleated red cells are fairly numerous in 

 the films, about forty in each. Their perinuclear protoplasm is in smaller amount than 

 usual and apparently also softer, as the outline of the cell is nearly always irregular, 

 while that of the red corpuscles is regular. Many red corpuscles stain more deeply than 

 the rest, and some only of these have an irregular surface. 



On the 25th day one large cell was seen in seven preparations. Nucleated red cells are 

 less numerous than in the films of the previous day ; about fifteen were seen in each film. 



On the 26th day two large cells were seen in two preparations of blood, one in each. 

 The one cell measured 26 m by 11 m, and from one side of it there projected a nucleated 

 bud, 10 im in diameter. The whole cell had a yellow tinge. Only two or three 

 nucleated red cells were found in a film. 



On the 28th day one or two nucleated red cells were found in each film ; and two 

 plain preparations of blood showed two large cells, somewhat below the average size. 



On the 29th day the dog was killed. 



Tlie Spleen was 3|- inches in length and weighed 16 '7 grammes. It was of a dark 

 red colour, of firm consistence, and was not very vascular. Fresh preparations and films 

 showed several giant cells and a fairly large number of nucleated red cells and erythro- 

 blasts ; all these kinds of cells were distinctly more numerous than in similar preparations 

 of the previous spleen. Amoeboid movement was not seen in the giant cells, which were 

 examined in aqueous humour on the warm stage. 



(Preparations of the Bone-Marrow showed numerous giant cells ; but none were seea 

 in films made from the Lymph Glands.) 



In sections of the Spleen there was seen a comparatively small number of giant cells, 

 on a rough computation about 250 in each. They have the ordinary characters of giant 

 cells in a not very active condition, that is, their nuclei show little budding and there are 

 relatively few mouth-like openings at their surface. The knobs projecting from the 

 central nuclear heap are sometimes seen to be the rounded ends of short thick pyriform 

 buds. Their protoplasm has a well marked yellow tint. There are considerable numbers 

 of erythroblasts and nucleated red cells in the pulp, by no means so many as in the 

 spleens of the three former dogs, but more numerous than in the immediately preceding 

 spleen. There occur in the veins not a few nucleated red cells. The follicles, whose 

 germinal centres are relatively large, contain a considerable number of pigment-holding 

 cells, but there is little pigment in the pulp. Occasionally a protoplasmic knob of a 

 giant cell, and sometimes an erythroblast, has the colour of pigment, due probably to 



