50 RESEARCH IN PROTOZOOLOGY 



glands to secrete either acid or ferments. The contents consist of 

 water and huge quantities of saHva mixed with the partially trit- 

 urated food of the animal, which under ordinary farm conditions 

 consists of either succulent or dried green plants and grain. The 

 plants supply cellulose and lignin fibers and chlorophyll. The re- 

 action of the fluid varies, according to the authors' experience, 

 from slightly acid to markedly alkaline, depending upon the 

 amount of succulent green feed the animal receives, and perhaps 

 other factors also. This fluid serves, under normal conditions, as 

 an ideal medium for the growth and multiplication of infusoria, 

 flagellates, amoebae, and bacteria. It should be clearly understood 

 that the protozoa are not to be confused with free-living forms, 

 for they constitute a fauna more or less specific to ruminants. 



The INFUSORIA of the stomach of domestic ruminants belong to 

 four families. In the ophryoscolecid^ are the three important 

 genera, Ophryoscolex^ Entodinium, and Diplodinium. Dogiel 

 (1927) recognizes the genus Epidinium Crawley, with one species 

 and numerous varieties in domestic ruminants, as separate from 

 Diplodinium. He likewise divides the genus Diplodinium into the 

 subgenera Anoplodinium, Eu diplodinium, Polyplastron, and 

 Ostracodinium — each with a number of species. The International 

 Rules of Zoological Nonienclature, Article 9, states: "If a genus 

 is divided into subgenera, the name of the typical subgenus must 

 be the same as the name of the genus." Dogiel has disregarded 

 this rule ; hence a correction will be necessary here. In the second 

 family, isotrichid^, are the genera I so trie ha with two species and 

 Dasytricha with one. In the family buetschliid.e is the genus 

 Buetschlia with its three species. The only ruminant representa- 

 tives of the PARAisoTRiCHiD^, SO commou in the horse, are Charon 

 ventricull Jameson, 1925, and Blcpharocorys boi/is Dogiel, 1926. 

 There is a possil)ility that they are synonyms. The authors have 

 found C. vcntriculi in cattle, but not B. bozns. For descriptions, 

 keys, and figures of the ophryoscolecid^, the best and most com- 

 plete work to consult is the monograph by Dogiel (1927). A gen- 

 eral account of the isotrichid^ and buetschliid^, as well as of 

 certain of the ophryoscolecid^, with references to other works, 

 will be found in the report by Becker and Talbott (1927). J. Buis- 

 son (1923) has also pubHshed a useful work. 



Dogiel's tables show that in cattle sixty-five species and vari- 

 eties (forms) of ophryoscolecid^ are found; in sheep, thirty- 



