66 COCCOPHYUEE. 
divisions it is probable that many of the groups, if they do not form new 
individuals, sooner or later become disintegrated, and the Fudorina thus 
eventually perishes. 
When, however, the process of impregnation takes place, the division 
stops at the second stage, that is when the Ludorina consists of 32 cells 
of the largest kind, each of which is about 1-1866th of an inch in dia- 
meter within its capsule, which is therefore a little larger. The process 
is as follows :— 
At a certain period after the second stage has become fully developed 
the contents of the four anterior cells respectively present lines of dupli- 
cative subdivision, which radiate from a point in the posterior part of the 
cell (in the subdivision of other cells the lines of fissiparation tend 
towards the centre of the cell). These lines, which ultimately divide 
the green contents of the cell into 64 portions, where the division stops, 
entail a pyriform shape on the segments, from whose extremities a mass 
of cilia may be observed waving in the anterior part of the cell of the 
parent, while yet her own pair of cilia are in active motion, and her eye- 
spot still exists in situ on one side of her progeny, thus showing that the 
latter may be almost fully formed before the parent perishes. At length, 
however, this takes place, and the progeny (Spermatozoids) separate from 
each other, and finding an exit, probably by rupture, through the effete 
parent cell and her capsule, soon become dispersed throughout the space 
between the two large ovoid cells mentioned, where they thus freely come 
into contact with the capsules of the twenty-eight remaining, or female 
cells. 
The form of the spermatozoid now varies at every instant from the 
activity of its movements, and the almost semifluid state of its plasma. 
Its changes, however, are confined to elongation and contraction ; hence 
it is sometimes linear-fusiform, or lunular, at others pyriform, short, or 
elongate. ‘The centre of the body is tinged green by the presence of a 
little chlorophyll, while the extremities are colourless, the anterior one 
bears a pair of cilia, and there is an eye-spot a little in front of the middle 
of the body, also probably a nucleus. It is about 1-2700th of an inch 
long and about one-fifth as broad. 
Once in the space mentioned, the spermatozoids soon find their way 
among the female cells to the capsules, of which they apply themselves 
most vigorously and pertinaciously, flattening, elongating, and changing 
themselves into various forms as they glide over their surfaces, until they 
find a point of ingress, when they appear to slip in, and, coming in con- 
tact with the female cell, to sink into her substance as by amalgamation. 
This author explains that there was some difficulty in seeing the act of 
union, but of the act itself he entertained no doubts. Zudorina in this 
stage also may frequently be seen with all the four anterior cells absent, 
and only a few spermatozoids left, most of which are motionless and 
adherent to the capsules, indicating that the rest have disappeared in the 
way mentioned. Lastly, many Hudorine in this stage may be observed 
with not only the four anterior cells absent, but with hardly a spermato- 
zoid left, indicating that the whole had passed into the female cells or 
had become expended in the process of impregnation. 
What changes take place in the Hudorina after this he had not been 
able to discover. At the time the female cells appear to become more 
opaque by the incorporation of the spermatozoids, and the crenulated 
state of the postericr part of the envelope in this stage seems also to in- 
dicate an approach to disintegration. 
While undergoing impregnation the female cells always contain from 
2 to 4 nuclei, as if preparatory to the third stage of development into 
which they are sometimes actually seen passing, with the spermatozoids 
present and scattered among them; but the effect of impregnation 
generally seems to arrest this stage, and thus save the species from 
that minute division which leads to destruction. 
