DESCRIPTIONS OF NEW HAEMOPROTOZOA FROM BIRDS IN N.S.W. 95 



easily be found amongst them, probably representing im- 

 mature and differentiating spermatozoa. 



Measurements. — The long forms varied in length from 

 25*5 to about 20/s their breadth being only '5/*. The short 

 forms varied from 18 to 13/* in length, and from 1*3 to '5/* 

 in breadth. The usual length was about 22/*. The differ- 

 ences in length are mainly due to differences in the number 

 and amplitude of the undulations which varied from three 

 to seven : five being most common. The long sperms were 

 almost straight. 



Resemblances to Spirochaete-trypanosomes.— In some 

 ways these were striking. For instance, the delicate 

 pointed end succeeded by a centrosome-like body were 

 very similar to the posterior end of a trypanosome with its 

 'centrosome.' Then from this body, could be definitely 

 traced in some cases, the origin of the axial filament which 

 traversed the body apparently on the edge of a surrounding 

 delicate protoplasmic coil, an appearance highly suggestive 

 of the flagellum of the trypanosome arising from its cen- 

 trosome and following the undulating membrane. In fact, 

 practically the only point of difference between these 

 spermatozoa as represented in Giemsa stained films and 

 very delicate trypanosome bodies lay in the absence of any 

 sharply defined nucleus in the former. 



References to Diagrams I, II, and Plates I, II. 



Diagram I — Figs. 1— -15, Halter idium ptilotis; various specimens 

 met with, indicating relative sizes of parasites and distribution 

 of pigment. 



Fig. 9, no pigment discernible. 



Fig. 11, very coarse pigment. 



Fig. 13, vacuole at one end. 



Figs. 16-25, H alter idium philemon. 



Fig. 16 showing vacuole. 



Fig. 18, very large form. 



Figs. 19, 22, young forms. 



