ON THE TRYPANOSOME OF THE LITTLE OWL. 
171 
eluded this to be the case. If the figures given in the 
preceding memoir of the large forms of T. fringi 11 inarum 
are compared with figs. 10 and 24 accompanying of the 
corresponding type of the parasite of the little owl, it will 
be noted that the general cytoplasm in the former appears dis- 
tinctly wider in proportion to the length of the body than in 
the latter trypanosome, although this is really a larger 
(longer) species. It may be mentioned that in one of the 
figures (fig. 48, pi. 5) which Zupitza (loc. cit.) gives of the 
large trypanosome identified by him with “T. ziemauni” 
from Eurystomus afer, showing an individual that is mani- 
festly flattened out, the cytoplasm also shows distinct bands. 
As regards the significance of this appearance we think 
it is probable that the clearer, lighter longitudinal zones, 
which are usually the narrower, may correspond to the 
position of the myonemes, though they do not, of course, 
actually represent them. The myonemes themselves are 
most probably fine but definite lines; apparently they 
are not easily demonstrable in Giemsa-stained prepara- 
tions. One of us ( 13 ) was fortunate to secure a preparation 
of T. percae, made by the wet method, which showed 
the myonemes well, but even in the case of the large T. 
raise, in iron-haematoxylin-stained films, we were unsuccess- 
ful ( 14 ) in seeing them ; also in none of our wet preparations 
of the larger forms of the trypansome of the owl have we 
been able to make them out. 
Of the three types or phases of the trypanosome above 
described, which occur together in the bone-marrow, and 
there alone, the small forms are the most numerous, the big 
blue individuals are distinctly less frequent, while the slender, 
medium-sized type, in its most fully developed condition with 
the long, narrow aflagellar prolongation is least common, and 
occurs somewhat scantily. 
As already indicated, these three phases can be definitely 
connected with one another by means of transitional forms 
which occur. Thus the medium-sized, slender parasites 
arise from the small ones by growth and extension of the 
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