128 The N.Z. Journal of Science and Technology. [June 
The nuclei of the halteridia were usually central in position and stained 
well. Melanin granules were generally situated in clumps towards the poles 
of the parasite, and were more numerous in the female gametocytes. 
Differentiation between the male and female gametocyte is determined by 
the staining reaction of the cytoplasm, which is darker in the female, and 
of the nucleus, which is somewhat larger in the male. 
A count of 400 consecutive parasites showed the following percentages : 
Male gametocytes, 30 per cent. ; female gametocytes, 70 per cent. 
A few erythrocytes were observed showing multiple infection, and in 
no instance did the number of parasites in a cell exceed three. Occasion¬ 
ally two adult parasites were encountered in a cell; in these cases the host 
cell showed abnormality of contour. The largest infected cell measured 
12*8 /x in length by 8/x in breadth, and harboured two adult parasites— 
a male and a female gametocyte. 
Description of Sir Successive 
Adult Parasites. — (1.) Protoplasm 
pale blue ; nucleus pale pink, cres¬ 
cent-shaped, central in position; five 
granules of melanin towards one end 
and four towards the other. 
(2.) Protoplasm dark blue; 
nucleus purple, oval in shape and 
situated towards one end of the 
parasite ; eleven granules of melanin 
at one end and nine towards the 
other. 
(3.) Protoplasm pale blue; 
nucleus purple, appears as a broad 
band, central in position ; four 
granules of melanin at each pole. 
(4.) Protoplasm dark blue, 
showing slight vacuolation ; nucleus 
unstained ; six granules of melanin 
in centre of parasite and two 
granules at each pole. 
(5.) Protoplasm dark blue, show¬ 
ing marked vacuolation ; nucleus 
composed of several faintly staining 
pink strands situated near centre of parasite ; seven granules of melanin 
at one end and four towards the other. 
(6.) Protoplasm dark blue; nucleus unstained; sixteen granules of 
melanin scattered. 
During the systematic examination of blood-films from hundreds of 
birds, all of which were either shot or captured in the North Island, 
malaria] parasites were recorded in the native ground-lark ( Anthus novae- 
zealandiae''') and in three species of imported birds—namely, song-thrush 
(Turdus musicus), blackbird ( Turdus merula), and in the skylark ( Alauda 
arvensis ). Wherever possible the blood examination was supplemented by 
an examination of the bone-marrow. No other parasites were detected : 
this is interesting in view of the findings in other countries. In England 
* A. B. Dore, The Occurrence of Malaria in the Native Ground-lark, N.Z. Journ. 
Sci. Tech., vol. 3, pp. 118-19, 1920. 
Fig. 2. — Halteridium of the skylark. 
A, B, and C, multiple infection of 
erythrocytes. 
