H. B. Fantham 373 
destruction of epithelial cells of the digestive tract; it is probably not 
of a serious nature. 
IV. General Morphology. 
The youngest stage in the life-cycle of the Schizogregarine is that of 
the sporozoite (Figs. 1, 3, i) a minute, protoplasmic body with a distinct 
nucleus. It is usually somewhat sickleshaped, and measures 5y to 12/j. 
in length. As it does not differ markedly from the sporozoite of other 
Gregarines (collectively known nowadays as Eugregarines) its detailed 
structure need not be further considered. The sporozoite attaches itself 
by its rostrum or pointed end to an epithelial cell of the gut or lining of 
the Malpighian tubule, and grows. During this period of growth the 
parasite absorbs nutriment from its host, and it is known as a trophozoite 
(Minchin, 1903, p. 156). The shape of the trophozoite varies, and as 
in Ophryocystis, and to a less extent in Schizocystis, it is quite different 
from that of the other Schizogregarines and nearly all Eugregarines, 
it will be well to consider separately the trophozoite of each genus. 
Ophryocystis. 
The sporozoite iu Ophryocystis grows, becomes pyriform and applies 
itself to the surface of the epithelium (Fig. 1, II). It then sends out 
stiff processes which serve to attach the parasite to the epithelium of 
the Malpighian tubules of the Coleopteran host. The trophozoite 
becomes somewhat conical in shape, and, while growing, its primitive 
single nucleus divides, so that it becomes multinucleate (Fig. 1, in). 
It is now known as a schizont, for cytoplasm gathers around each 
daughter nucleus and then the whole schizont (Fig. 1, iv) divides 
into small, uninucleate, somewhat pyriform masses (Fig. 1, v) termed 
merozoites (“ schizozoites ” of Leger). These migrate into the lumen 
of the tubule, and later attach themselves between new host cells 
by means of their processes, and so start a new infection in the 
same host. The multinucleate schizonts, which divide by multiple 
fission, are termed by Leger “mycetoid schizonts” (Fig. 1, m), to 
distinguish them from another form of schizont to be noted presently. 
The “mycetoid schizonts” somewhat recall the trophozoites of Myxo- 
sporidia in general appearance, but the resemblance is merely superficial. 
There is probably no close genetic relationship between these “ mycetoid 
schizonts ” and the Myxosporidia. 
