504 NOTES ON SOME PARASITIC PROTOZOA, 



(a) Male gametocyies (fig.lb). — Protoplasm shows very pale 

 staining or none at all. In one there were thirteen masses of 

 melanin, larger than in the female type, and, though fairly evenly 

 distributed, grouped more towards the poles of the host-nucleus. 

 The host-nucleus was distinctly displaced. In another, the 

 melanin granules were similarly large, fairl}' evenly distributed, 

 though tending to form three groups, one towards each end and 

 one in the middle, the nucleus not as yet displaced. 



(b) Female gametocytes(^g.lQ). — Protoplasm decidedl}' stained. 

 In two specimens, the pigment appeared as twenty-four to thirty 

 masses, smaller than in the male form but larger than we have 

 seen in other Australian Halteridia, more or less uniforml}' dis- 

 tributed, though in one with a tendency to be more numerous 

 towards the end of the parasite. The host-nuclei in these were 

 pushed to an almost lateral position, and the parasites occupied 

 the whole of the host's protoplasm save a narrow band on the 

 distal side of its nucleus. In another example, the pigment was 

 more aggregated into three groups towards the two ends and in 

 the middle of the parasite, the parasite was not quite so large, 

 and the host-nucleus less displaced. 



(c) The only intermediate form seen (fig. 17), perhaps a three- 

 quarter grown schizont,had the protoplasm staining intermediately 

 between the other two forms, with smaller granules at each end 

 and a few^ in the middle. 



The size of the corpuscles of this bird were 12 5 by 7/i, the nuclei 

 of the corpuscles 5 by 3/x, and the parasite 18 (measuring along 

 the middle and around the bends) by 4/x. 



Blood-films from two birds were examined, the parasites 

 occurring only in one. 



We propose for this parasite the name Halteridium nettionis, 

 the specific name being derived from the generic name of the 

 host. 



The type-slide has been presented to the Australian Museum^ 

 and the co-types are being retained b}'' the Bureau. 



