THE INTESTINAL FLAGELLATES OF INSECTS 253 



tation tests, as well as a study of the general morphology to the 

 study of specificity of protozoa. A certain amount of work of the 

 nature had already been done on trypanosomes and malaria organ- 

 isms, but not in any such extensive and thorough fashion. 



Referring again to the flagellates of muscoid flies, Noguchi 

 (1926) found physiological dififerences between three strains of 

 them. The flagellates //. inuscidaritin from Musca doniestica, H. 

 media and H. parva from CaUiphora sp. ? each reacted strongly 

 with its own antisera in the agglutination and complement fixation 

 tests, but not with the serum of another, thus proving the sero- 

 logical independence of the three strains. This physiological inde- 

 pendence was further confirmed by the sugar fermentation tests. 

 These three so-called species differed likewise in morphology. From 

 a study of the plates one may recognize in H. muscidanim a typical 

 H. miisccc-domcsticcc, as described in detail by Prowazek (1904). 

 H. media seems to be identical with H. ealliphorce Swellengrebel. 

 Incidentally, it is possible that Wenyon (1913) was studying 

 mixed infections of H. muscce-domestica; and H. ealliphorce. H. 

 parva may possibly be the same species which the writer (1923) 

 described and figured as one of three types. In fact, it appears that 

 the three species figured by Noguchi are the same as the three 

 types described and figured by the writer (1923, pp. 199-200). 

 Noguchi's technique should be applied to the true Herpetomonas 

 muse ce-dome Stic ce (as ascertained by cytological study) to see 

 whether dififerent strains of this type, as obtained from different 

 species of flies, show identical or different physiological behavior. 



It would perhaps be desirable to rework the muscoid fly flagel- 

 lates first, but any one or more of other groups could be used in 

 the same manner. The importance of correlating careful morpho- 

 logical studies with any and all experiments carried out must be 

 stressed. The Schaudinn-iron-hematoxylin technique is a valuable 

 one. 



From the evidence submitted there appears to be ample reason 

 for believing that more than one species of Herpetomonas is pres- 

 ent in muscoid flies, and if future work confirms this belief, how 

 shall the species be named? The writer (1923) and Hoare (1924) 

 have reviewed the history of nomenclature of the flagellates of 

 house-flies. We can be sure that Burnett did not apply any specific 

 name. Leidy referred to fly flagellates, without describing them, as 

 Bodo museariim. Stein is responsible for the name Cercomonas 



