192 Haeniogregarina anarrhichadis 
protoplasm of these oval forms in their earliest stages stains very 
faintly, so that sometimes the contour of the parasite is discernible only 
by contrast with the surrounding protoplasm of the host cell. Later, it 
takes on a distinct pale blue stain, with irregular and ill-defined areas 
of condensation scattered here and there (figs. 6, 7, 9), and, as the 
haemogregarine gets older, the colouring of the protoplasm deepens into 
a dull purple tint (fig. 8), while the more deeply staining patches 
of condensation become more marked. As a rule the pi’otoplasm shows 
no granulation. Once only (fig. 4), the broader pole was found to be 
occupied by a ring of fine granules. Not infrequently this pole is 
occupied by one or two large clear vacuoles (figs. 6, 10). But much 
more characteristic is the gradual development in this broader pole 
of some pui'ple staining substance, at first staining faintly (fig. 5), but 
soon staining more and more deeply, until it finally appears as a purple 
black mass, more intensely stained even than the chromatin granules 
of the nucleus. This substance varies in shape from a thin crescent 
the horns of which run up the sides of the haemogregarine (figs. 3, 8, 9), 
to a large semilunar mass which completely fills up the broader pole 
(figs. 6, 10). This appearance is a still more marked feature of the 
larger forms of the haemogregarine. 
Type 2. (PI. VIII, figs. 11 to 20.) 
This phase is longer and much thinner than the foregoing. The 
length varies from 8‘5 yu. to 9 /a, with an average of 8'7 /a. The breadth 
ranges from 1'5^ to 3ya, the average being 2'.5 ya. One extremity is 
usually slightly more pointed than the other, and the parasite as a 
whole is bent so as to be comma-shaped. The nucleus, which lies in 
the pointed extremity, averages 3’2 ya in length, and thus takes up more 
than a third of the total length of the parasite. The nuclear chromatin 
granules are considerably smaller and do not stain quite so deeply as 
in the case of type 1. The protoplasm, particularly in the thinner 
foi'ins, takes on a dull purple tint (figs. 11 to 15). The clubbed 
extremity of the haemogregarine is filled with the deeply staining 
substance before mentioned, which may take up a quarter or even a 
third of the total length of the parasite. This substance frequently 
ends abruptly on the nuclear side, being sharply demarcated, by a 
straight line, from the rest of the parasite. The vacuoles occurring in 
the later phases of type 1 are here but rarely seen, and when seen are 
often indistinct in outline. 
