342 H. M. WOODCOCK. 
Flagellates. I first observed this condition in some of the large 
female individuals, in which it appears as seen in text-figs. 1— 
3. lying close to the ordinary nucleus, generally in contact 
with it, isa much smaller body, which stains much more deeply 
than the large one, at times appearing almost black (K.). This 
little body is generally ovoid or round, but in some cases tends 
to have a rod-like shape. ‘There is no possibility of confusing 
this nuclear body with a large pigment-grain, or a collection 
of grams. It hes usually near to the outer surface of the 
body. In parasites of the indifferent type this nuclear 
element, which I homologise with a kinetonucleus, is larger 
TEXT-FIGsS. 4-6, 
Indifferent forms of Halteridium. 4and5. From heart blood, 
smeared straightway. 6. From peripheral blood, after addition 
of a drop of salt-citrate solution, and interval of a couple of 
minutes before smearing. A. Kinetonucleus, or kinetonuclear 
element. J. Trophonucleus, or trophonuclear element. x 
2500. 
and may approximate to the size of the other nucleus (tropho- 
nucleus). It may be round (text-fig. 6) or, frequently, it is 
more or less dumb-bell-shaped (text-fig. 5), as if it were com- 
posed of two halves. It is important to note that this nuclear 
dimorphism can be readily recognised in many of the minute 
forms, the kinetonucleus being a small, deeply-staining grain 
lying close to the ordinary nucleus, generally at one side (text- 
fig. 12). This feature gives several of these small individuals a 
striking resemblance to the resting-phases described of various 
Herpetomonadine parasites, 
