OBSERVATIONS ON TRYPANOPLASMA CONGERI. 487 



I should like to take this opportunity of tliauking- Mr. 

 Ehnhirst, the director of the Marine Station at Millport, for 

 his assistance in getting material, and Miss Robertson for 

 help in the drawing of the figures. 



Methods. 



The stages figured in this paper were all obtained on wet 

 smears from the stomach wall, fixed either in Flemming or cor- 

 rosive acetic. Both of these methods gave excellent results. 

 The films were stained in Giemsa, Tworfc, iron-ha3matoxylin 

 and eosin, and Mayer's acid heemalum and eosin. All these 

 stains gave satisfactory results, but the figui'es were all drawn 

 from preparations made either with hasmalum and eosin, or 

 irou-hiematoxylin and eosin. 



Morphology of the Active Form. 



As there seems to be a certain amount of discrepancy 

 amongst different authors in regard to the nomenclature of 

 the various structures in trypanosomes and trypanoplasmas, 

 I have indicated in the following diagram the nomenclature 

 I have decided to adopt. It is pi-actically that used by 

 Minchin in his paper on the structure of Trypanosoma 

 lewisi in relation to microscopical technique (^ Quart. Journ. 

 Micros. Sci.,' vol. 53, 1909, p. 799). 



The normal active Trypanoplasma congeri has rather 

 an elongate body, measuring roughly IS jn by 2*7 ju. The two 

 flagella arise apparently from a single basal granule near the 

 anterior end of the kinetonucleus ; the anterior flagellum 

 passes np the mobile beak to end freely, while the posterior 

 flagellum passes transversely across the body of the animal, 

 a,nd running down in connection with the narrow undulating 

 membrane, projects freely for a distance of about 10 ^tt beyond 

 the animal's posterior end. As regards the basal granule, 

 most previous observers seem to have been of the opinion 

 that each flagellum in Trypanoplasma arises from a 



