236 The Philippine Journal of Science mz 



when encountered in this state it dies quickly. After death the central 

 sphere soon disappears. 



3. The size of Blastocystis varies greatly and the larger they grow the 

 smaller becomes the peripheral fringe of cytoplasm. Living blastocysts 

 are relatively small and rich in cytoplasm. 



4. The blastocysts of the cases mentioned here, although having some 

 general characters in common differed much as to details of structure. 

 This difference was especially marked when the associated parasites were 

 different. No blastocysts were found without an associated parasite. 



5. The occurrence of blastocysts in the stools of a man fed on milk 

 and eggs only, and the presence of living blastocysts in the man's stools, 

 exclude the idea of their being remains of solid food. 



6. It is probable from the observation recorded in this paper, that 

 "Blastocystis" is not the name of a zoological genus but of a peculiar form 

 of degeneration to which representatives of different genera of intestinal 

 protozoa may be liable. The resemblance seen in blastocysts from dif- 

 ferent sources which may lead to their being regarded as belonging to 

 one species is easily explained by a convergence resulting from the para- 

 sites which produce blastocysts losing their characteristics during the 

 process of degeneration. 



7. No certain stages of sporulation were seen as described by Alexeieff, 

 and the nuclear structure, although variable, never resembled that given 

 in his description. It is therefore probable that Alexeieff's Blastocystis 

 enterocola is different from the form described in man under the same 

 name. 



Chatton (9) also has done some recent work on Blastocystis, and 

 while his preliminary paper does not directly bear on Tricho- 

 monas, his account, coupled with his figures, are very suggestive 

 in connection with the work of Hadley, Kofoid and Swezy, and 

 others. His work is largely confirmatory of that of Prowa- 

 zek(43) on Bodo (Heteromita) lacertse, but the host studied by 

 Chatton was the Barbary gecko, Tarentola mauritanica. The 

 appearances he notes are similar to those mentioned by other 

 writers. He failed to secure a glycogen reaction in the vacuole 

 whose contents he assumes to be of protein nature. Alexeieff 

 laid some stress on the presence of glycogen in determining the 

 bodies to be of blastomycetic nature, but it must be borne in 

 mind that the cysts of Entamoeba at times contain glycogen. 

 Chatton describes the formation of flagellated cells within the 

 microspheres. He has also seen the coupling of these flagel- 

 lates, a performance probably similar to that described by Had- 

 ley, but he did not see subsequent fusion. Therefore he thinks 

 the existence of copulation at this stage very probable. 



Turning to trichomonad infections in man, there seem, in 

 view of the foregoing, to be at least two important observations : 

 namely, those of Castellani on Entamoeba undulans(T) and of 

 Gauducheau on the unity of Trichomonas and Entamoeba.^) 



