602 G. II. IMJKW ANI> W. I»K :\i(>i;(;AN. 



musculiir tissiit^, whicli sliowed signs of degeneration in its 

 soinewliiit swollen fibres and faint striation. 



When a blood-space had been entered, bacteria were often 

 seen ingested by the blood-coi-pnscles, but in later stages it 

 was obvious that tlie number oF bacteria was so out of pro- 

 portion to the number of corpuscles that they could not all 

 be removed by phagocytosis, and were of necessity distributed 

 all over the body in the blood-stream. 



During these processes the fibroblasts in the walls of the 

 blood-spaces, and in the intermuscular connective tissue in the 

 neighbourhcod of the implanted mass, undergo rapid division. 

 This rapid division, resulting from the i-eaction of the tissues 

 to the irritation caused by implantation, appears to be always 

 amitotic. Mitotic division was onlv observed in much later 

 stages, when the source of irritation had been removed by 

 phagocytosis, and the rate of division of the fibroblasts was 

 much slower. 



Before amitotic division the fibroblasts lose their spindle 

 shape and become oval ; a split then appears at one emi, and 

 progresses in the plane of the long axis of the nucleus until 

 two daughter nuclei are formed, attached to each other at one 

 extremity, and inclined at an acute angle to one another. 

 These gradually straighten out until they form an hour-glass- 

 shaped mass of nuclear material. Finally the two nuclei are 

 separated at the constriction and become almost cii-cular in 

 shape. 



As a result of this active multi})lication of the fibroblasts, 

 the strands of connective tissue bounding the blood-spaces 

 and forming the intermuscular connective tissue become 

 crowded with nuclei. The bodies of the fibroblast cells 

 become very indistinct, and little beyond rows of elongated 

 nuclei is discernible. As the multiplication becomes more 

 rapid the typical spindle shape of the nuclei is lost, and they 

 become first oval and finally circular. 



There appears to be a constant migration of these cells 

 with round and oval nuclei, towards the site of implantation. 

 They have very little cytoplasm, and from this, and their 



