C. A. Hoare 
323 
The structure of the body of the main form (Figs. 22, 23, 24, 25) differs 
considerably from that of the preceding. The protoplasm of these forms has 
a distinct alveolar structure and contains some kind of indefinite accumula¬ 
tions. The nucleus of these forms has lost its definite shape and appears in 
the form of minute chromatin granules disposed in different ways, but chiefly 
in the form of a transverse band. 
A similar alveolar structure of the protoplasm was described by Noller 
(1912), Reichenow (1910), Schubotz (1913), and others, in schizonts, and the 
arrangement of the nuclear elements in the form of a transverse band is found 
in parasites described by Langmann (1899), Billet (1907), and Flu (1910), 
also in the period of their maturation. Both these data and the configuration 
of the present form, as well as its dimensions, perhaps indicate that we are 
dealing with a full grown schizont. 
As regards the mutual relations between the forms described, they present 
a fairly complete picture of gradual growth from the young parasite to the 
stage of schizont. 
Form 2 (Fig. 19) indubitably presents a merozoite which had only recently 
penetrated into the blood corpuscle. It is exactly such a form that is described 
as typical for the merozoite by those authors who had the opportunity of 
studying the complete cycle of development of haemogregarines (Reichenow, 
1910, 1912, and others). By degrees, as it grows, this form begins to elongate 
(Fig. 20), thicken and bend over with one end (Fig. 21); this end at length 
reaches the opposite extremity (Fig. 22), and the parasite assumes the shape of 
a U. From this moment begins the alteration in the structure of the proto¬ 
plasm and the nucleus of the parasite pointing to the phenomena of multiplica¬ 
tion. In this period both limbs begin to fuse together (Fig. 23), and, finally, the 
massive oval form (Figs. 24, 25) characteristic of the schizont is produced. 
It is interesting to mark certain peculiarities in the disappearance of one 
of the limbs of the doubled parasite, usually preceding the formation of the 
mature schizont. This process may be effected in two ways: 
1. The tail gradually shortens and appears to be drawn into the main 
portion of the body. This course was described by Reichenow (1910) in 
H. stepanowi , and also takes place in the haemogregarine described by me 
above (Fig. 14). 
2. The tail bends over and grows to the length of the main portion of the 
body, and then both limbs fuse along the whole line of their contact. Such a 
course was described by Simond (1901), and Woodcock (1912). This pheno¬ 
menon is also observed in the parasite just described (cp. Figs. 20, 21, 22, 
23, 24). 
In conclusion I shall dwell briefly upon a disputed structure common to 
nearly all haemogregarines, this structure having been termed by various 
authors “ the light area” or “rim,” “membrane,” “cyst,” and “capsule.” 
With regard to this element various opinions have been expressed. 
