PROCEEDINGS OF THE SOCIETY. 
253 
Mr. C. L. Curties exhibited and briefly described a new removable 
mechanical stage which had been suggested by Mr. Allen, which he 
thought would be found to possess some advantages over others now in 
use. One of these was that, being attached to the side of the stage, 
there was a clearer space for the slide than if fixed on the top. It had a 
movement of one inch in each direction, which was ample for all ordi- 
nary purposes, and being divided, the position of a specimen could be 
quickly logged. The way in which it was attached, viz. by one screw 
above and one below the stage, rendered it very steady, but easy to 
remove. The construction was simpler than in the usual Mayall stages, 
and this would reduce the cost. He placed it in the hands of the Fellows 
to be passed round for their personal inspection. 
The President thought this arrangement might be regarded as a 
simplification and an improvement upon the well-known Mayall mechani- 
cal stage. One of these improvements was its increased steadiness ; in 
using the Mayall stage, he found that when the milled heads were moved 
there was always a little shake which made the slide jump on the stage ; 
but in this new form the bearing of the vertical movement was very long, 
which made the movement quite steady. A further advantage also arose 
from the method of fastening the mechanical to the edge of the ordinary 
stage ; this increased the breadth of the stage, and enabled an extra long 
slip to be used if desired. 
The thanks of tbe meeting were voted to Mr. Curties for bringing 
this stage for exhibition. 
The President said they had also received from Mr. Philip Jourdain, 
for exhibition that evening, two lenses which were known as Cooke 
lenses for photography ; their chief use was for making enlargements of 
comparatively large objects. They were not, properly speaking, Micro- 
scope lenses, because in comparison with these their aperture was 
small, but regarded as photographic lenses their aperture was large. He 
had no doubt that they would be very valuable in taking low-power 
photographs, and were certainly worth the attention of persons who did 
work of this kind. He was sure the Society would appreciate the 
kindness of Mr. Jourdain in sending these new lenses for exhibition. 
The thanks of the meeting were voted to Mr. Jourdain for sending 
these lenses for exhibition. 
Mr. C. F. Rousselet read a short note with reference to his method 
of mounting Rotifera, a process which he had carried out with such suc- 
cess that he now had a collection of about 400 slides comprising nearly 
300 different species. He had been induced to attempt the mounting of 
these creatures in such a way as to preserve their natural form and ap- 
pearance, from the felt want of reliable specimens with which to com- 
pare those which were obtained from time to time by microscopists ; all 
previous attempts in this direction having resulted only in failure to 
preserve the objects in such a way as to retain any resemblance to the 
natural aspect of the living creature. The details of the process of 
killing, preserving, and mounting having been already published, Mr. 
Rousselet made only a brief reference to these, but he called special 
