96 RESEARCH IN PROTOZOOLOGY 



amoebse from the rats and infected kittens with the same, produc- 

 ing an acute amcebiasis hke the infection produced in kittens in- 

 fected with E. Jiisfolytica of man. He also produced the same type 

 of acute symptoms in kittens infected with E. histolytica-like 

 amoebse from naturally infected rats. 



He does not consider these amoebae from naturally infected rats 

 to be morphologically or physiologically dififerent from E. histoly- 

 tica of man and proposed E. histolytica variety murina as a termin- 

 ology for differentiation. This use of a varietal or racial term to 

 indicate the host in which a parasite is found, was previously sug- 

 gested by Chandler (1923) and appears to be a very satisfactory 

 solution to a difficult problem when actual morphological differ- 

 ences are apparent. When morphological differences are not appar- 

 ent, however, this system could not be used, since the trionym indi- 

 cates well-established morphological differences and cannot be used 

 to indicate merely a difference in environment as would be indicated 

 by adding a host's name to a parasite morphologically indistin- 

 guishable from another. 



This difficulty might be overcome by the use of the Latin ex 

 plus the common name of the host or the scientific name of the 

 host in which the parasite was found, e.g., 



E. histolytica ex mure — the type found in rats and mice 

 E. histolytica ex macaco — the type found in Macacus monkeys 

 E. histolytica ex sue — the type found in the domestic pig. 

 To clutter up the literature with an unlimited number of new 

 species names just for the sake of having one's own family name 

 appear after them does not seem to be justifiable and the only pos- 

 sible excuse for such a habit is the second one given by Hegner 

 (1927), i.e., ''because of the value of a specific name for reference 

 purposes." The suggestion made above appears to be preferable 

 to naming new species of parasites indiscriminately merely on the 

 basis of finding them in a new host as has been the practice adopted 

 by some authorities. It retains the advantage of association of a 

 parasite with a definite host and at the same time indicates a 

 definite morphological similarity to a known type. 



lodaiua^ba 



Natural infections of rats with lodamceba have not been re- 

 ported. Kessel (1923a) and Smith (1928), however, record hav- 

 ing infected rats experimentally with lodanweba williamsi of man. 



