468 J. R. BRADFORD AND H. G. PLIMMBB. 



this fusion process generally occurs, it takes place in the 

 blood itself. In these spleen less animals the bone marrow 

 is always affected, and always contains quantities of the 

 amoeboid form, which is not ordinarily the case in normal 

 animals. 



As regards the life of the Trypanosoma outside the 

 body there is at present little to say. Laveran succeeded 

 in keeping them alive in blood kept at 0° C. for as long 

 as three mouths. We have kept them alive in thin films 

 for six days after removal from the body. We have also 

 kept a large quantity of blood containing them in an 

 atmosphere of oxogeu, and have found that, although the 

 adult forms soon disappeared, with the formation of tangles, 

 plasmodial masses, and then amoeboid forms, the blood 

 was infective for three days at least, at which time our 

 experiment came to an end. 



In the ordinary way the blood of animals loses its in- 

 fectivity in a few hours after deatli, as decomposition sets 

 in with great rapidity in this disease. 



X. EXPLANATION OF PLATES 24 AND 25, 



Illustrating Messrs. J. E. Bradford and H. Gr. Plimmer's paper 

 " On the Try pauosoma Brucii, the Organism found 

 in Nagana or Tse-tse Fly Disease.''^ 



All these figures were drawn under a Zeiss 3 mm. apochromatic objective 

 of N.A. 1"40, usedwiili a Zeiss acliromatic condenser of N.A. 1"0, and with 

 compensating oculars of various powers, which will be indicated when referring 

 to each figure, or set of figures, separateK'. The specimens were all stained 

 by the method described in the paper. 



Tigs. 1 — 4 (Oc. 8). — Ordinary adult organisms from rat's blood on fourth 

 day, stained liglitly to sliow the general shape and structure, a. micronucleus ; 

 b. vacuole ; c. macronucleus. 



There are three red corpuscles, diawn with Figs 1 — 9 from rat's blood 

 under Oc. 8, to show the relative size of the organism. 



