APPENDIX ON PROTOZOOLOGY 733 



APPENDIX ON PROTOZOOLOGY, 



Comprising Notes on Recent Researches, Formulae of some 

 Culture Media, and Brief Notes on General Protozoological 

 Technique. 



BY 



H. B. FANTHAM, M.A., D.Sc. 



I. NOTES ON RECENT RESEARCHES. 



SINCE the foregoing section on Protozoology was sent to press, 

 certain interesting observations and results have been published. 

 Brief notes on such, and some references thereto, are now added. 



It is necessary, however, to remark that sometimes it is impossible 

 to give a precise or rigid definition to a genus of Protozoa, owing to 

 differences of opinion, to differences regarding nomenclature or to 

 incompleteness of knowledge. Such a lack of definition, while incon- 

 venient for the time being, is not unhopeful, as it directs attention to 

 the necessity for further work, which is inevitable in such a relatively 

 new and wide subject as protozoology. Thus, it may be noted in 

 illustration that Minchin, in 1912, in his text-book regarding the 

 genus Entamceba writes : " The entozoic amoebae are commonly 

 placed in a distinct genus, Entamceba, distinguished from the free- 

 living forms by little, however, except their habitat and the general 

 (but not invariable) absence of a contractile vacuole." 



Differences between Entamceba histolytica and E. coll. In 

 continuation of the remarks on pp. 34 and 40, it may be added that 

 Lugol's solution (iodine in aqueous potassium iodide solution) in 

 fresh specimens shows by brownish staining the presence of glycogen 

 in the vacuoles of Entamceba coli. Such a reaction is rarely or never 

 given by E. histolytica. 



Phagedaenic Amoebae. Carini and others record cases in which 

 the skin around an operation wound in connection with liver abscess 

 became gangrenous. Amoebae, possibly Entamceba histolytica, were 

 found therein and may have been responsible for the gangreno- 

 phagedaenic action. 



Endamceba gingivalis (see pp. 43, 44). Smith and Barrett, 1 after 



1 Journ* of Parasitol., i, p. 159. 



