103 



Halteridium, sp. from Myiagra nitida (Fam. Muscicapidct). 

 Plate xxvi., figs. 1-5. 



In an imperfectly-prepared blood-film from the Leaden 

 .Flycatcher, Myiagra nitida, shot at the Hawkesbury River 

 in November, 1909, Halteridia were detected in the red cells. 



The parasites possessed the typical form, and invested 

 the host nucleus very closely, but did not displace it. Their 

 size was about 0*01 mm. by 0*002 mm. They were thus 

 much smaller than those seen in some other birds, e.g., 

 Zosterops co&rulescens.. The pigment was usualty aggregated 

 towards one end, but parasites were seen in which it was more 

 dispersed. In all cases there were relatively few granules. 

 No enlargement of the host cell was recognized. 



Halteridium, sp. from an Owl, Ninox boobook (?). 

 Plate xxvi., figs. 7-15. 

 In July, 1910, Dr. T. L. Bancroft, of Brisbane, kindly 

 forwarded to us blood-films from an owl shot near Bris- 

 bane. These contained in relative abundance a Halteridium 

 which, to our view, seems to differ from the other forms we 

 have met with in Australian birds. 



Male and female gametocytes were readily recognizable, 

 and, in the accompanying descriptions of eight consecutive 

 specimens examined, a re-arrangement has been made by which 

 male forms are first taken, and female forms are concluded 

 with : — 



(1). Protojolasm pale-blue ; nucleus pale-red, elongated; 



14 scattered melanin granules. 

 (2). Parasite more towards one end of host cell ; this end 

 of parasite broader, other end narrowed : proto- 

 plasm pale-blue ; nucleus pale-red, rather concen- 

 trated ; 11 scattered melanin granules. 

 (3). Protoplasm pale: nucleus pinkish, elongated; 8 

 melanin grains towards one end, 1 at other, with 

 another grain nearer centre, 2 opposite nucleus. 

 (4). Parasite towards one end of host cell: protoplasm 

 pale ; nucleus pinkish , elongated : 3 grains of 

 melanin beyond centre at one end, 2 coarser grains 

 towards other end, 2 coarse ones near centre. 

 -(b). Parasite towards one end; nucleus pale-pink, 

 elongated ; 6 grains of melanin towards one end, 

 2 towards other end, 6 coarser ones opposite 

 nucleus along outer edge. 

 (6). Protoplasm a little deeper blue; nucleus pale-pink, 

 ' elongated ; 2 masses of melanin towards one end, 

 4 towards other. 



