360 



Labbe" described for halteridium a process of multiplication in the red 

 corpuscle which has never been confirmed. He stated that the nucleus of 

 the parasite divided into a number of small nuclei placed at the two ends of 

 the halter- shaped body, which then divided up into two bunches of small 

 merozoites. It is, of course, possible that tho development may differ 

 in different species. But it is more probable that the supposed nuclei at 

 the ends of the body are merely metachromatinic grains, possibly the 

 " alkaliphilous " granules described by Mayer (685, p. 234). 



3. The Leucocytozoa. The true leucocytozoa that is to say, 

 the species of the genus Leucocylozoon of Danilewsky are only 

 known to occur in the blood of birds, as stated above ; they must be 



B 



FIG. 158. Leucocytozo&n ziemanni from the blood of the Little Owl, Athene noctua. 

 A, Male, B, female, C, young form. N., N., nucleus of the parasite ; JV 1 , N 1 , 

 nucleus of the host-cell. Original ; magnification 2,000. 



distinguished clearly from the pseudo-leucocytozoa of mammals, 

 which are in reality haemogregarines, and will be dealt with as such 

 below. The leucocytozoa of birds are found in the blood as bodies 

 usually elongated and spindle-shaped, sometimes, however, rounded 

 in form, which represent each a gametocyte, male or female, con- 

 tained in its host-cell (Fig. 158). The exact composition of these 

 bodies is, however, a little doubtful ; it is not quite certain where 

 the host-cell ends and the parasite begins. The centre of the body 



24 



