288 Dr. L. Rogers. Development of Hepatomonas of [Oct. 16, 



both in the absence of all trace of undulating membrane and in the position 

 of the micronucleus or blepharoplast at the anterior flagellated end of the 

 organism, although in addition they obtained forms showing the development 

 of the membrane by the passage of the blepharoplast back towards, and 

 then past, the macronucleus, until it arrived near the posterior end of the 

 organism, and a typical trypanosome resulted v When further experience of 

 my culture failed to reveal any forms with a complete or even partial 

 undulating membrane, the question arose whether it was not an organism 

 distinct from the trypanosomes, although closely related to it, such as a 

 hepatomonas in which no undulating membrane is present. In my last 

 paper I left this an open question, while stating that nothing had yet been 

 found which might not be an incompletely developed trypanosoine ; a view 

 which has also been adopted by both Christophers (10) aud Leishman(ll). 

 The more abundant and uniform development of flagellates in the acidified 

 medium have enabled me to study closely innumerable apparently com- 

 pletely developed long free forms, in a stage in which they show extremely 

 active movement in fresh specimens ; but still no trace of an undulating 

 membrane, or even a tendency for the micronucleus to pass away from the 

 anterior end of the organism towards the macronucleus has ever been 

 observed, although seen by Novy and MacNeil in their cultures of bird 

 trypanosomes. I therefore conclude that the organism I have been able to 

 develop belongs to the order Hepatomonas and not to the trypanosomes, and 

 I propose to name it the Hepatomonas of Kala-azar. At the same time I 

 prefer to limit the term kala-azar to the epidemic-spreading form of the 

 disease as seen in Assam, and to retain the term " cachexial fever " for the 

 less fatal sporadic affection, if only for the sake of avoiding the unnecessary 

 cruelty of having to tell sufferers from the milder disease that they are 

 suffering from the greatly dreaded kala-azar. 



Degenerate Forma. 



I have already pointed out that the absence of bacteria is necessary for 

 the continued development of the flagellated stage of the organism, and that 

 cocci especially are inimical to its growth. In one of my most active recent 

 cultures staphylococci gained access to the tube on the seventh day of the 

 culture during its repeated examination, and the degenerating changes 

 resulting were readily followed. On the following day fresh specimens 

 showed that all motion of the flagella had ceased, although on staining many 

 of the organisms showed little or no change. Others, however, were granular 

 and stained more lightly, while some were becoming shorter and more oval or 



