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be distinguished by the possession of two flagella and a much 

 larger nucleus than is found in species of Trypanosoma. The genus 

 Trypanosoma is parasitic in all classes of vertebrates, but Try- 

 panoplasma is only found in fishes. In fresh-water fish, however, 

 both genera may be found parasitic together. In fact, this is 

 more usual than to find only one type. The easiest method of 

 obtaining specimens is to take a common eel alive, and kill it 

 by a blow on the head with a blunt instrument. Take a drop 

 of blood from the heart as quickly as possible, as the blood of 

 fish coagulates much more rapidly than is the case with mammals, 

 and put under cover-slip. The blood dries round the edges, and 

 so seals up the enclosed film. In the case of a Norfolk Broad 

 eel, well infected, after 24 hours specimens prepared as just 

 described were still active, at 48 hours slower, and at 72 hours 

 nearly moribund. If, after putting on cover-slip, the prepara- 

 tion is at once sealed with vaseline, these organisms have such 

 extraordinary vitality that they will live and even divide. The 

 President had had some alive for nine days in this condition. 

 An extensive range of size and structure had been noted in 

 Trypanosoma in fish, and particularly in the eel, where all stages 

 are found. In the pike, two sizes only, large and small, are 

 common ; in the perch three forms are found. Trypanoplasma 

 also shows dimorphism. It has been suggested that the large 

 and small forms may possibly correspond to male and female, 

 and the intermediate the form from which male and female 

 develop. It was mentioned that there were many problems 

 still unsolved relating to the life-history of these protozoa. The 

 current idea as to the method of infection of fish was that the 

 trypanosomes were carried by leeches. Unfortunately, there 

 was no monograph or general handbook to British leeches of 

 later date than 1846, so that there was great difficulty in 

 identifying species. He would suggest that some member or 

 members of the Club take this matter up. Concluding his 

 remarks, the President said that his investigations had been 

 made during the last two summers at the Sutton Broad labora- 

 tory, a private laboratory owned by Messrs. Eustace and 

 Robert Gurney. It was near Catfielcl, and was a most delight- 



