320 Natural History Bulletin. 



Another more extended examination on . the warm stage 

 was made March 7th. At first very little amoeboid move- 

 ment of any kind was visible, probably because of the shock 

 and the altered environment. After about ten minutes had 

 elapsed, sluggish movements began to take place. All sizes 

 of leucocytes showed amoeboid movement. The larger cells 

 moved much more rapidly than smaller, and all cells showing 

 any considerable degree of locomotion were of large size, the 

 small cells showing slight changes of outline. 



Blood Plaques. 



In every preparation examined without reagents, many 

 leucocytes seemed to contain coarse granules in one hemi- 

 sphere. Sometimes these aggregations of granules appeared 

 to be crescentic, from the turning of the leucocyte. A number 

 of these granule-like bodies were seen lying in masses in 

 the plasma. At first I thought these independent masses of 

 granules were, the result of disintegration of leucocytes. A 

 higher power revealed the fact that these granules were 

 blood plaques. The coarsely granular appearance of one por- 

 tion of certain leucocytes was due to the fact that blood 

 plaques were adhering to the surface of the leucocytes. In 

 no other specimen of blood examined by the writer have 

 these blood plaques been so numerous or so conspicuous. 



SUMMARY. 



In the leukiemic blood the average diameter of one hundred 

 corpuscles was jA? of an inch, which, although slightly larger 

 than the average usually taken for coloured corpuscles, can 

 not be considered to vary much from those in a state of healths 

 The largest were ss'ug of an inch, the smallest, aside from the 

 minute corpuscle described, were z^\v of an inch. 



The number of coloured corpuscles per cubic millimeter, 

 estimated by counting those in one hundred squares of the 

 haemacytometer, was 4,188,000, about 80 per cent, of the 

 number found in normal blood. The haemoglobin was esti- 



