462 SUMMARY OF CURRENT RESEARCHES RELATING TO 



verrucosa was living, till there were equal parts of fresh and salt, led 

 to the disappearance of the contractile vacuole. She was led to this 

 and similar experiments, which require further extension, from a study 

 of marine Heliozoa, in which there is no contractile vacuole. 



Trypanosoma congolense.* — A. Laveran inoculated a goat with 

 T. congolmse, and re- inoculated it after its recovery. The second attack 

 was mild and the cure rapid. Two subsequent inoculations had no 

 result, the goat had become immune. But a subsequent inoculation with 

 T. dimorphon was followed by a well-marked infection. Therefore he 

 concludes that T. congolense and T. dimorphop are distinct species. 



* Comptes Kendus, cxlvi. (1908) pp. 853-6. 



