364 



sickness. Bruce furnished the proof of the causal 

 connection of this trypanosome with the disease. 

 Bruce further showed that the disease was trans- 

 mitted by a particular 'tsetse' fly, Glossma palpalts. 

 It has since been shown that the trypanosome in 

 this disease is identical, morphologically and in 

 its pathogenig properties, with T. gambiense. In 

 fatal cases a streptococcus can often be isolated 

 from the organs, but death may occur with all the 

 typical symptoms and yet the organs be completely 

 sterile ; so that the streptococcus occurs only as a 

 terminal infection. 



1. Blood examination. — Parasites may be 

 absent from the peripheral blood for a month or 

 more at a time, and even if abundant, seventy to 

 a cover-slip, may again completely disappear. 

 The number of parasites bears no relation to the 

 severity of the symptoms. 



2. Cerebrospinal fluid. — Obtained by lumbar 

 puncture. Seldom more than one to five trypano- 

 somes occur in the centrifugalized sediment. 



3. Cervical lymphatic glands. — Greig and 

 Gray state that trypanosomescan be most certainly 

 found by puncturing the cervical glands. 



4. Post-mortem. — Parasites are often found 

 in the pericardial, pleural, and peritoneal fluids 

 even without centrifugalizing. 



T. gambiense is from 18-25 m in length, by 

 2-2"8 M broad. It occurs in two main forms — (i) a 

 ' long form ' with a pointed posterior end, and (2) 

 a short stumpy form with many chromatic granules 

 {Vide Plate V). 



Pathogenic action. — It is pathogenic for many 

 mammals, e.g., rats, guinea-pigs, rabbits, monkeys 

 (except Cynocephalus), etc. On the whole, the 



