56 



RESEARCH IN PROTOZOOLOGY 



colon can be taken to the laboratory for study in a thermos bottle or 

 jug kept at about 37° C. Ten per cent formalin is a good fixative 

 for killing and preserving the infusoria. 



The best general works on these ciliates are Fiorentini (1890), 

 Bundle (1895), Gassovsky (1919). Strelkow (1928) published a 

 paper on the genus Cycloposthmin only. The junior author is now 

 preparing a monograph on the protozoa of the cecum and colon 

 of the horse in which a number of new species will be described. 



The known species of infusoria from the horse fall into four 

 families which are listed below with their genera. 



Family 



I. BUETSCHLHD^ Pochc, I9I3 



2. PARAisoTRiCHiD^ Cunha, 1916 



3. CYCLOPOSTHID^ Pochc, I9I3 



4. PODOPHRYID^ Collin, 191 1 



Genera 

 Didesmis 



Btmdleia (formerly Buetschlia) 

 Blepharoprosthium 

 Blepharosphcera 

 Blepharocottus 

 Holophryoides 



Paraisotriciha 



Blepharocorys 



Blepharozoum 



Prorodonopsis 



Blepharocodon 



Paraisotric h op sis 



Cycloposthium 



Tripalniaria 



Tetratoxum 



Cochliatoxum 



Ditoxum 

 ^ Triad inium 

 ' Spirodinium 



^ Allantosoma 



From his title it appears that da Cunha (1917) has found a 

 Bolantidium in the horse. The authors have been unable to procure 

 the paper to confirm this opinion, but if it is true the problems of 

 specificity and host specificity again arise. 



In connection with the protozoa of the horse there are a number 



of problems which are practically identical with those relating to 



the protozoa of ruminants, but which will probably be found to be 



much more difficult to solve. This is because of the difficulty of 



' Placed in these families at least temporarily. 



