374 



an arborescent appearance is noticed, due to the 

 .deposit of a white tissue (macrophages containing 

 parasites) in the centre of the lobules. 



Large intestine. — Extensive multiple ulceration 

 is almost constantly present. Fungating granu- 

 lation tissue occurs in association with the ulcers. 

 Purulent peritonitis, broncho-pneumonia, septic 

 infarcts, are commonly met with. The other organs 

 show no particular change to the naked eye. 



MICROSCOPICAL CHANGES 



1. Make thin smears of spleen pulp, liver, 

 bone marrow, lung, kidney, testis, lymphatic gland, 

 suprarenal. Stain with Romanowsky. Parasites 

 occur in immense numbers in the spleen, liver, and 

 bone marrow. To a less extent in the lungs and 

 testis. They are present also in the suprarenals 

 and lymphatic glands. 



2. Make thin smears from granulation tissue 

 of ulcers of the skin and intestine. Parasites are 

 present in both situations ; in the skin they are 

 scanty, in the intestine they may be very numerous. 



3. Place small pieces of these tissues on cover 

 glasses. Harden in alcohol or corrosive sublimate. 

 Embed in paraffin. Cut sections. Stain by the 

 modified Romanowsky niethod (p. 51), or with 

 haematein. The study of sections is essential for 

 a clear understanding of the relation of the 

 parasite to the tissues. Observe the following 

 conditions : — 



Liver. — In the lumen of the capillaries of the lobule, often 

 applied closely to the capillary wall, occur numerous large 

 cells crowded with parasites. These cells are sometimes 

 retracted and globular, but more usually they are characteristic- 

 ally extended, and suggest the idea that they are actually 



