190 PROCEEDINGS OF SOCIETIES. 
two attached frustules; the bead-like expansions are marginal. 
In the front view in the centre of the upper margin there is a 
remarkable depression ; corresponding with this on the side view 
there is a region with curvilinear boundaries. Besides this pecu- 
liarity, there is in the side view a remarkable difference between 
the present form and S. wnipunctata, the latter being elliptico- 
lanceolate, the former linear-oblong. Mr. O’Meara proposed for 
this form the name Striatella curviseptata. 
Mr. Vickers exhibited a fine diatom, Eupodiscus Rodgevi, for- 
warded by Mr. Stokes. 
Dr. John Barker exhibited a new plan, constructed from his 
design, for placing a number of slides under the microscope and 
bringing them one by one in succession quickly under view. This 
consists of a large disc of wood, with a number of round openings 
, near the circumference, of about an inch in diameter, over each of 
which a slide is placed and retained in its position, with the object 
over the aperture, by an elastic ribbon passed through some small 
holes in the disc. The disc itself is fastened to the stage by a 
piece of projecting brass-work made to fit and hold in the central 
opening of the stage, and projecting out beyond the stage in 
front, and bearing the pivot or axis adapted to the centre of the 
disc, and on which it revolves. This apparatus could therefore be 
made to follow the stage movements, and would be suitable, of 
course, for opaque or transparent objects. It would be very ad- 
vantageous for a class, for the purpose, during a demonstration, of 
bringing a series of slides quickly under view. 
Mr. Archer exhibited fine examples of Ameba villosa (Wallich), 
but he now drew attention to this seemingly not uncommon 
form, in order to show a remarkable addition to the usual charac- 
teristics of this organism. ‘This was the presence of a large and 
numerous tuft of very long prolongations, commonly issuing from 
just beside the villous patch. These prolongations, which formed 
a compact bundle, were slender, linear, often as long as the - 
ordinary length of the animal, about the middle often with a slight 
groove-like constriction or narrowing, their ends terminating 
abruptly. Seemingly nine out of ten of the specimens in this 
gathering possessed these appendages, giving them a yery re- 
markable and curious appearance. Under alow power and ata 
hasty glance these Amcebe appeared as if each carrying posteriorly 
a whole bundle of straight bacillar objects, seemingly immersed in 
their substance ; under so low an amplification and hastily viewed, 
it might be thought almost like a bundle of Nitzschie or rigid 
oscillatoriaceous filaments stuck into the posterior end of the 
Ameeba (pincushion-like) by some external foreign force, and as 
if as many as possible had been made to go into one spot. But 
upon examining these curious fasciculi under a higher power 
more closely, he thought it could readily be seen that they were 
not composed of foreign bodies either issuing from or penetrating 
