96 University of California Publications in Zoology [Vol. 16 



there be in it of merit or value is due chiefly to his kind and helpful 

 suggestions and to the interest he always showed therein. My acknowl- 

 edgments and thanks are also due Mrs. Purington for her valuable 

 help with my drawings and to Mr. E. B. Talt of Albany for his kind- 

 ness and thoughtfulness in aiding me to obtain the material for this 

 work. 



Techniqtte 



The material used in this work was obtained at Mr. Talt's ranch 

 at Albany, thirty minutes from the laboratory by car. Because of 

 the difficulty of obtaining material at frequent intervals and because 

 of the large amount that could be obtained from one horse, the caecum 

 of which frequently contained as much as five gallons of semi-fluid 

 food, it was both necassary and po.ssible to obtain material for study 

 in the living and fixed condition from the same host. The methods 

 of procuring the material are essentially the same as those described 

 b.y Dr. R. Gr. Sharp (1914) in his paper on Diplodinium ecaudatum. 



In every case extreme care was taken to avoid any fall in the 

 temperature of the caecal fluid between the time of killing the horse 

 and studying the living material. This was equally true of the fixed 

 material. That the material was well fixed was shown by the fact that 

 protozoans were obtained with cilia extended and without contractions 

 or contortions of the body. 



Schaudinn's alcoholic sublimate and Zenker's fixing fluids, used 

 hot, gave uniformly the best results. When followed by Heidenhain's 

 iron-alum haematoxylin or Delafield's haematoxylin. with a counter- 

 stain such as eosin, acid fuchsin or erythrosin, in toto mounts were 

 obtained which gave a clear differentiation of the nuclear and cyto- 

 plasmic structures. 



In my study of the eiliates from the caecum of the horse I have 

 identified the following forms previously reported from Italy or 

 Germany: Cycloposthium bipnlmatnm (Fiorentini) Bundle, Parai- 

 sotricka colpoidea Fiorentini, Didesmis avails Fiorentini, and Didcsmis 

 quadrata Fiorentini 



I have found no forms corresponding to the following species: 

 Blcpharocorys uncinata (Fiorentini) Bundle, Blepharocorys valvata 

 (Fiorentini) Bundle. Blcpharocorys unifasciculatum (Fiorentini) 

 Sharp, and Blepharocorys jubata Bundle (1895). 



However, as .stated above, I find a form which combines the generic 

 characters as described by Bimdle (1895) for Blepharocorys, but does 



