212 RESEARCH IN PROTOZOOLOGY 



A few words must be said of the yeasts and fungi of the intes- 

 tinal tract. These organisms have been reviewed as a group by 

 Anderson (1917). His paper includes a large bibhography. He 

 discusses Parasaccharoniyccs asJifordi which many regard as the 

 cause or at least an important contributing cause in psilosis or 

 sprue. No student of intestinal disorders should neglect to ac- 

 quaint himself with some of the literature on sprue. Ashford's 

 paper on the etiology of the disease (1917) should be read as an 

 introduction to the subject. The papers of Christian (1925), New- 

 ham (1926), and of Reed and Ash (1927), are of equal impor- 

 tance. 



Because of its superficial resemblance to the cysts of amoebae, 

 Blastocystis is a source of confusion and error to the inexperi- 

 enced. Lynch (1922) recognizes two and possibly three species 

 and in a later paper (1923) suggests that it may be pathogenic. 

 Other writers have voiced the same opinion, but there really is 

 little, if any, evidence in support of this. It is of almost universal 

 occurrence in the stools of persons living in the tropics and is 

 very common elsewhere. As in the case with the flagellates it 

 appears in increased numbers in loose and diarrheic stools. This 

 coincidence is worth pondering upon. 



With the possible exception of the sprue organism there appears 

 to be no evidence implicating any of these forms in intestinal 

 pathology. However, Blastocystis is still suspected by some of 

 being pathogenic and its position in this respect should be finally 

 determined. 



It is a matter of real importance, however, to define the cellular 

 picture seen on the rupture of the intestinal abscesses in schis- 

 tosomiasis (bilharziasis). The problem is similar to that presented 

 by intestinal involvement in malaria and kala-azar. Several writers 

 have mentioned the general character of this exudate, but the best 

 account I have so far seen is that of Faust and Meleney (1924). 

 Bahr (1918) brings out a few points that should be borne in mind. 

 The discovery of the ova of the parasite will, of course, define the 

 primary condition. The problem is to establish the general char- 

 acter of the exudate so it may be distinguished from that of an 

 intercurrent amoebic or bacillary dysentery which might proceed 

 to a fatal termination under bilharzia treatment. 



