68 Proceedings of Philosophical Societies. ° (Jury, 
At the same meeting a paper by Sir Everard Home, Bart. on the 
respiratory organs of some genera of vermes that live in water, was 
read. These organs consist of a number of openings on both sides 
of the neck, which lead into spherical or flattened balls. Water 
passes through these openings into the bags, and is afterwards 
thrown out again. The reason why the water does not enter at 
the mouth as in fishes, is because these animals, as the leech, re- 
quire their mouths for suction, either to procure food or to fasten 
themselves to other bodies. 
On Thursday the 8th of June, a paper by Dr. Brewster was read 
on the multiplication of images and colours which accompany 
them in some specimens of Iceland spar. ‘Towards the end of the 
session of the Royal Society, the number of papers presented is 
usually so great, that only a small portion of them can be read to 
the Society. On this account nothing can be added to the notice 
of Dr. Brewster’s discovery relative to this subject given in the last 
number of the Annals of Philosophy. 
At the same meeting a paper by C. Babbage, Esq. was read, en- 
titled, On the Calculation of Functions. This he informed us is a — 
new species of calculus, which will require new methods of investi- 
gation. But as only the introduction of the paper was read, it is 
impossible to give any farther account of it. 
At the same meeting a paper by Dr. Herschell on the satellites 
of the Georgium Sidus, with some observations on the space pene- 
trating power of telescopes, were also read. The object of the pa- 
per was io furnish data to astronomers to determine the number 
and orbits and periodical times of the satellites of this very remote 
planet. He described the orbits and periods of two of the satel- 
lites, supposed that another existed within them, and probably three 
others without them. 
On Thursday the 15th June, a paper by Sir Everard Home, Bart. 
was read, on the mode of generation of the lamprée and myxine. 
He found by a great many dissections at different perieds during 
the summer, that these animals are all hermaphrodites; those, 
which were supposed to be males, producing eggs as well as the sup- 
posed females. 
At the same mecting a paper by Anthony Carlisle, Esq. was 
read, on the connection between the extravascular and vascular 
parts of animals. Hair, feathers, nails, hoofs, are extravascular 
substances, and possess no vessels. The chief object of the paper 
was to show, that the shells of shell-fish and snails are likewise 
without vessels. ‘They cannot be injected. ‘Their membranes do 
not exhibit the same appearance as those that contain vessels. 
When a piece of snail-shell was broken off, the injury was repaired 
by a viscid substance applied internally, and then layers of calea- 
reous matter were laid over it. 
At the same meeting a paper by John George Children, Esq. 
was read, on the effects of a very large galvanie battery. It consisted 
of 20 pair of zine and copper plates 6 feet long and 2 feet 6 inches 
