16 
LIPS, IN' ITS LOWER FORMS. 
fine granules, some larger globules, probably of oil (fat), a 
contractile sac anteriorly, and an elliptic discoid granular 
nucleus, often accompanied by another smaller, finely 
granular, discoid globule, well defined. 
“ The larger nucleus is the one destined to undergo the 
first change ; this it does by the development of fine cilia 
around its periphery, which actively vibrato, and so cause 
its rotation. Whilst this goes on, it increases in size, ad- 
vances towards the anterior of the Acineta, which takes on 
active contractions, and thereby ultimately ruptures its 
integument, allowing the embyro (ciliated nucleus) to 
escape. On its emergence, the embyro swims away rapidly 
by means of its cilia ; what further changes it undergoes 
are yet to be discovered. 
“ However, the part the Acineta body has to perform is 
not completed by the production of the one embryo ; but 
the same process has to be repeated again and again, until 
its formative granular mass is used up, when the Acineta 
becomes a contracted, shrivelled, empty sac, seated upon 
the persistent stalk. 
“After an emission of an embryo, the Acineta body 
contracts strongly ; some of its diverging fibres shorten, 
whilst others are entirely withdrawn. This contracted 
condition, after lasting for a time, relaxes; the Acineta 
resumes its usual movements ; the fibres spread out 
anew, moving about as usual in various directions ; and 
it finally regains its original characters, save that it is 
smaller, and, instead of a smooth, even surface, it has its 
tunic thrown into folds or undulations. The spot from 
whence the embyro escaped soon becomes imperceptible.”'’"' 
* Condensed from Stein, ia Pritchard’s Uist. of Infut. Animate., p. 531. 
(Ed. 1852.) 
