generally four longitudinal lines running down its sides, which 
lines seem to be due to so many extremely narrow folds or 
creases ; these become, indeed, sometimes obliterated when the 
auimal becomes more than usually broadened out, but they 
again appear on its reassumiug its somewhat pear-shaped figure, 
and during active progression. It was curious to observe the 
vigorous flow of the granules down the middle of the body for 
about two thirds of its length, when they seemed to become sud- 
denly arrested, and quietly lay by to one or other side, thus leaving 
the anterior one third and a portion of each lateral margin of the 
animal hyaline; from the anterior margin the very broad and 
shallow, lobe-like pseudopodia became extended, whilst at the 
opposite or posterior end occurred the nucleus and vacuole, ex- 
actly as described by Carter. As in other forms which agree 
with this in admitting of an anterior and a posterior end being 
discriminated, such as A. Umax and A. villosa — the pseudopodia 
being given oft’ only at one end — the progression of this form was 
pretty rapid, and executed in tolerably straight lines or slight 
curves, thus calling to miud the movements of the curious amoeboid 
bodies described by Mr. Archer in StephanospJiccra pluvialis, in 
which instance, however, these consisted of the modified primor- 
dial cells of that curious organism. Dr. Barker had bad these 
specimens tolerably abundantly in a gathering, in which they lasted 
some six weeks, without undergoing any change. Their minute- 
ness and comparative hyaline character rendered them, however, 
somewhat readily overlooked. 
Rev. E. O’Meara showed RJiizosolenia robusta. 
Mr. Archer showed a really copious gathering of the Poly- 
chaftus he had brought forward at a previous meeting, and ven- 
tured to describe as Polycluetus spinulosus. A dip from this 
gathering would sometimes show six or eight of this very elegant 
rotatorian in one field ; in fact, tw r o or three dips would probably 
disclose more specimens of this form than he had, perhaps, seen 
altogether before. He regretted the pool (near Carrig moun- 
tain) whence these were taken had since dried up, especially as 
this fine species seems to be rather rare ; but still he thought 
that, if sought for, it must turn up in other similar localities. 
August 20 th, 1868. 
Dr. John Barker exhibited a rounded pellucid cyst, enclosing a 
number of the empty frustules of a Gomphonema, which w r ere 
quite destitute of contents — in fact, as clean as if prepared by 
acid. Dr. Barker, with whom Mr. O’Meara seemed to coincide, 
thought this must represent some phase in the history of the 
diatom, from which view Mr. Ai’cher was inclined to dissent, con- 
ceiving this “ cyst” rather to be that of some rhizopodous creature, 
and its germs discharged, and hence w r ould regard the diatoma- 
ceous shells as representing simply the indigestible remains of the 
animal’s last dinner. 
