382 Dr. H. L. Duke. Relation of Fowls and [May 9, 



plane of division is at right angles to the split in the kinetonucleus. In 

 some of the latest stages of the material, namely, those from the proventriculus, 

 this is .less apparent, and the kinetonucleus seems more compact ; still, even 

 here the double nature of the structure can still be detected in most cases. 



" The blepharoplast proper, i.e. the minute granule actually at the origin of 

 the flagellum, is usually obscured, but can be seen in favourable specimens. 



" Another structure not usually to be observed in trypanosomes, but 

 which I have seen in the development stages of T. raice, a massive 

 trypanosome not unlike T. gallinarum in appearance, is a granule situated 

 towards the posterior, i.e. antiflagellar, end of the cell. This granule is not 

 particularly small in size, but its outline is rarely very sharply defined ; in 

 some instances it appears to be attached by a fine line to the nucleus or 

 to the blepharoplast. In some individuals there are two lines visible, one 

 of which passes to the blepharoplast, the other to the nucleus. Owing to 

 the density of the protoplasm these lines are not very clearly visible, and 

 can be observed only in the more favourable specimens. 



" The granule, on the other hand, is a very fairly constant appearance, 

 and divides at divisions (figs. 1, 2, 4, and 9). In T. raice, in the develop- 

 mental stages in the leech, these appearances are much clearer and more 

 perfectly defined. In T. gallinarum the granule is not to be seen in the 

 more slender stages. 



" Figs. 1, 2, and 4 give an illustration of the more usual binary fission, the 

 spindle of the trophonucleus shows the characteristic centrodesmose, but 

 the finer details are never particularly clear. 



" In conclusion, I may say that, while I have not so far met with a mixed 

 infection, it appears that there would not be much likelihood of these forms 

 passing undetected ; nevertheless, crithidial individuals appearing in a cycle 

 of a mammalian trypanosome, where cocks' blood had formed part of the 

 food of the fly, would have to be rejected until confirmed from ffiies fed 

 exclusively upon clean animals. 



" Note. — From the nature of the above infections, it appears that Glossina 

 palpalis is certainly not the normal host of this trypanosome, and probably 

 not even a facultative host. It is interesting to note in this connection 

 that] a small Simulid fly (species so far unidentified) was found relatively 

 frequently on the fowls in certain parts of Bugerere. On one occasion at 

 Endeba, where the fly was more especially numerous, one specimen was 

 found well infected with a trypaniform flagellate. The fowls in the enclosure 

 were found to be infected with T. gallinarum. The flagellates in the Simulid 

 were of small size and mostly crithidial in type, though a few showed the 

 nuclear relations characteristic of trypanosomes. 



