jQ . HOWELL. [Vol. IV. 



we are in a position to explain the budding corpuscles of 

 Malassez. In several instances, when examining the marrow, 

 I have met with appearances which seemed to justify Malas- 

 sez's theory. Nucleated red corpuscles were seen with one or 

 more non-nucleated corpuscles apparently budding out from 

 them. Sketches of such cells are given in Fig. 3. They seem 

 to me, indeed, to be better examples, as far as the drawings 

 go, of the process of budding than those figured in Malassez's 

 (27) own paper. I cannot say that these examples of budding 

 are common ; on the contrary, I obtained them clearly only 

 in two cases, in both of which the notes of the experiments 

 record that the animal had been bled so severely that it did 

 not make a good recovery, but remained weak and anaemic; 

 and it is possible that this is sufficient to explain their occur- 

 rence. I was at first inclined to believe that we must admit 

 that, under certain conditions at least, new red corpuscles may 

 be produced by budding in the way described by Malassez. 

 But a simpler explanation of these forms suggested itself. 

 What seem to be examples of budding are most probably cases 

 of multiplication of nucleated red corpuscles by division, in 

 which the process was not carried out to the complete sepa- 

 ration of the newly formed corpuscles, though from one or 

 more of the new cells formed the nucleus has escaped, leaving 

 the non-nucleated corpuscle as an apparent bud on its sister- 

 cell. As evidence for this explanation, one may find in the 

 apparent buds granules of nuclear matter staining blue with 

 the methyl green, such as I have described as occurring some- 

 times in the newly formed red corpuscle after the extrusion of 

 its nucleus. Moreover, one frequently meets with two, three, 

 or more mature nucleated red corpuscles joined in a cluster 

 or chain as the result of recent division, and such as would 

 produce apparent examples of budding if one or more of the 

 cells lost their nuclei. This would be more likely to happen, 

 of course, in animals in which too severe a bleeding had im- 

 paired the processes of cell development in the marrow as in 

 the other tissues of the body. The explanation that I have 

 adopted seems to me to be preferable to supposing that in the 

 marrow new blood corpuscles are formed from the same cells 

 by two entirely different methods of reproduction. 



