426 WM. CECIL BOSANQUET. 
or, as it rather appeared in some cases, a lump of protoplasm 
towards the centre, with the granules which were originally 
there appearing in the midst of it. This explanation was 
suggested by Professor Lankester in the case of a somewhat 
similar appearance found by Miss L. J. Gould (5) in Pelo- 
myxa. However, in one instance there appeared to be two 
such formations in the same animal (fig. 5) ; in another, the 
whole central portion of the gregarine formed a distinct round 
mass, staining more darkly than the rest of the substance and 
divided off from it by a dark line, as to the nature of which— 
whether it were a definite membrane or not—I was exceedingly 
doubtful (fig. 6). Mr. Minchin suggests that the phenomenon 
is rather to be regarded as a preliminary to the stage of spore- 
formation, and it was he who applied to it the name “ capsule,” 
which I have used. But its nature must for the present remain 
obscure. 
Nucleus.—The nucleus ina teased fresh specimen appeared 
perfectly spherical, about 70 m in diameter, with a circular 
nucleolus dimly visible. It was quite colourless and trans- 
parent (fig. 7). In the process of hardening it invariably 
shrank, and in sections was always much crumpled. It was 
bounded by a membrane, which appeared double-contoured 
under a high power. The ground-substance was finely granular 
in appearance, and it contained as a rule two nucleoli, but 
sometimes more—in one instance as many as five (figs. 8, 9), 
The nucleoli were highly vacuolated, the vacuoles in some 
instances seeming to have some contents capable of being 
stained (fig. 10). 
Life History.—The following is a brief account of those 
stages in the development of this gregarine which I have been 
able to observe : 
Conjugation.—Conjugation first takes place, two round 
individuals becoming pressed and flattened one against the 
other, the cuticles of the two coalescing at the portions where 
they are applied one to the other. I have not been able to 
observe any mitosis in the nuclei, but in those cases in which 
the conjugating gregarines each contained a single undivided 
