April 21, 1870 | 
The rotatory movement of the planets upon their axis is an appli- 
cation of gravitation to their respective densities, and is equal 
to the time of revolution ofa satellite placed at a distance 1, 
multiplied by a co-efficient of resistance representing the density 
of the planetary body, which is at the same time the square root 
of the relation of its weight to the centrifugal force. The squares 
of these co-efficients are equal to the cubes of the distances at 
which satellites would gravitate in the period of rotation of each 
planet, and the distance at which a synchronous satellite would 
gravitate round each planet is the cube root of the centrifugal 
force, and marks the theoretical limit of any atmosphere. By 
applying his law to the planets Uranus and Neptune, the author 
deduced a diurnal rotation of 10% 40™ for the former, and of 
toh 58" for the latter.—Facts towards the history of nitric acid by 
M. E. Bourgoin, were commnnicated by M. Bussey. The author 
described the decomposition of nitric acid at different degrees of 
dilution by the galvanic current. He regarded the formula of 
nitric acid as NO®*, 2 H2O%, With the acid in-a very diluted 
state, only hydrogen was evolved from the negative pole; as the 
strength of the solution was increased the hydrogen evolved re- 
acted upon the nitric acid, and caused the production of ammonia, 
free nitrogen, deutoxide of nitrogen, and nitrous acid, according 
to circumstances. With 15 equivs. of water nitrous acid remains 
in solution.—M. H. Sainte Claire Deville presented a note by M. 
Deschamps, on the metallic tartrates, in which the author de- 
scribed the preparation and characters of a double tartrate of 
sesquioxide of manganese and potash, having the formula: 
Mn 202 KO, C8H4!0”, 4 HO-—M. P. Duchartre read some 
observations on the turning of certain fungi. The author de- 
scribed a case in which numerous examples of an agaric (pro- 
bably Cofrinus radians, Desmaz.) grew in perfect darkness from 
the bottom of a water tank, and consequently in a reversed 
Position. They were all upon the southern portion of the 
tank, but their stems sloped towards the north, and in the 
mature examples were bent upwards at an angle towards their 
summits, so as to bring the head into its natural position with 
the hymeneal lamellae downwards. The author cited also some 
experiments made with Claviceps purpurea, specimens of which 
placed in a reversed position curved upwards towards maturity, 
and thus brought their heads into the natural position. He con- 
sidered these observations, especially the former, to be strongly 
opposed to the mechanical theories of the direction of growth in 
plants.—A note was read by M. H. Baillon, on the dissemina- 
tion of the stones of Dorstenia contrayerva. The author noticed 
the structure of the fruit in Dorstenia and the allied plants, which 
he stated to consist of a number of small drupes. He stated 
that the parenchyma of each drupe is much more developed 
towards the base, and that the cells composing it acquire a great 
amount of elasticity, which, acting upon the stone when this is 
set free by the lesion of their upper part, projects it to a con- 
siderable distance.—M. Dumas in presenting M. Pasteur’s great 
work on the diseases of silkworms, gave an excellent summary 
of its contents ; and M. Guyon accompanied the presentation of 
his natural history of the chigoe (Rhynchoprion benetrans, Oken), 
with an elaborate analysis of the work.—M. Roulin communi- 
cated a note containing observations on the chigoe, supplemen- 
tary to M. Guyon’s remarks.—M. A. Dumeéril presented an 
account of the production of a white race of axolotls at the 
menagerie of the Museum, with some remarks on the transfor- 
mations of those batrachians. The white race of axolotls has 
been established by breeding from ordinary females with an 
albino male, and again breeding from pale-coloured females thus 
produced with the same male. Some of the white individuals 
have undergone their complete transformation. The author 
stated that hitherto the transformed axolots (Amé/ystoma) have 
never propagated, and that an examination of their sexual organs 
showed ova and spermatozoids in plenty, but not in the perfect 
condition. The generative products seemed to have undergone 
an arrest of development at the metamorphosis.—A note by M. 
E. Duchemin was read, describing a singular cause of the death 
of carp in a piece of water at Montigny. The fish thrive in this 
water, but every spring a considerable number are found dead, 
and all these are blind. This blindness is ascribed by the 
author to the attacks of toads, which fix themselves upon the 
heads of the fish, and do not quit their hold even when taken 
out of the water. As remarked by the Secretary of the Academy, 
this habit of the toad has been long known.—M. C., Robin pre- 
sented a note by M. Legros on the real origin of the secretory 
canals of the bile.—M. Guyon presented statistics of the cases 
of hydrophobia observed among Europeans in Algeria from 
NA TORE 
641 
1830 to August 1851.—A note on the operation of artificial pupil, 
by M. Liebreich, with figures of an instrument employed in the 
operation, was fcommunicated.—Of several other papers no 
particulars are given. 
BRUSSELS 
Royal Academy of Belgium, March 5.—The following 
papers were read :—r. On the Aurora Borealis in the months 
of January and Febuary 1870, by M. A. Quetelet.—z. On com- 
mensalism in the animal kingdom, by M. P. J. Van Beneden. 
The author distinguishes under the name of commensalism those 
cases in which one animal lives upon another, but not at its ex- 
pense. In the present paper he described some new examples 
of this phenomenon. On the authority of M. Alex. Agassiz, he 
noticed a Lepidonotus which lives near the mouth of Asteracanthion 
ochraceus, Brandt, a small Clea which resides among the 
fringes of a Pelagian Medusa (Dactylometa quinguecina, A. 
Agass.), a species of Hirudinea which lives in a Beroid 
(Anemiopsis Leydii), a Philomedusa, (named Biccidium by L. 
Agassiz) which haunts the buccal fringes of the great Gawea 
arctica, a Hyperina which infests the disc of the American 
Aurelia, and a Planaria (P. angulata Mill,) which attaches 
itself to the lower surface of the King Crab, near the base of the 
tail. M. Agassiz also states that the young Comatule like to 
affix themselves to the basal cirri of the adults. M. Van Bene- 
den also noticed, on the authority of Risso, that the Fishing 
Frog (Zophius) lodges a species of Murzenid (Apterichthys oculata) 
in its great branchial sac. He referred to the polype, which so 
generally coats specimens of //ya/onema, as furnishing an ex- 
ample of commensalism, and in connexion with /Zyalonema as a 
Sponge reaffirmed his opinion that Sponges represent the polype 
type reduced to its simplest expression ; a notion very like that 
which has lately been put forward by Hackel.—3. Remarks on 
the equation x"—1=o0, by M. E. Catalan.—4. Note on the 
nature of the sun, by M. G. Bernaerts, in which the author 
maintained that the sun consists of a gaseous nucleus covered 
with a thin, incandescent liquidlayerand luminous clouds.—5. On 
the meteoric stone which fell at Saint Denis- Westrem, near Ghent, 
on the 7th June 1855, by Dr. Stanislas Meunier. The author 
stated that the material of this meteorite, of which a portion, 
weighing 723 grammes, was picked up, is identical with that ot 
many others, including the meteorite of Lucé (1768), whence he 
proposes to call it Zwcézte. He gave the analysis of another stone, 
which fell in the Lower Pyrenees in 1868, and remarked upon 
the occurrence of /wcéite in various brecciiform meteorites, as- 
sociated in some with an oolitic mass which he denominated 
montrejite, from the stone of Montrejeau (1859), and which, in 
other meteorites occurs alone. The author maintained that the 
formation of meteorites is due to the natural breaking up ot 
larger celestial bodies at the close of their development, and that 
the moon is now approaching this stage of its existence.—6. On 
Bryonicine, a new nitrogenous substance extracted from the roots 
of Bryonia dioica, by MM. L. de Koninck and P. Murgart.— 
This was described as of a very pale, yellow colour, crystallising 
from dilute alcohol in slightly flattened and irregularly inter- 
mixed needles, neutral, insoluble in cold water, potash, ammonia 
and dilute mineral acids, soluble in alcohol, ether, &c., and in 
glacial acetic acid, and concentrated sulphuric acid, with the last 
giving a blood-red solution. The formula was stated to be C!9 
H16N?20°—7. Investigations on the embryogeny of the Crustacca, 
by Dr. E. Van Beneden.—In this paper the author described 
in detail the development of the genera Anchorella, Lerneopoda 
Brachiela and Hessia, the last-named a new genus.—8. Discovery 
of a deposit of phosphate of lime beneath the town of Louvain, 
by Prof. G. Lambert. This bed was discovered in 1869, in 
boring an artesian well ; it commenced at a depth of 105-50mm., 
and was 5 mm. in thickness, containing nodules of phosphate of 
lime like those worked for manure in this country. 
VIENNA 
Imperial Academy of Sciences, Feb. 17 (continued from 
p- 618).—11. Prof. Briicke communicated the results of 
his investigations of the digestive products of the albuminous 
bodies.—12. Experimental investigation on the diffusion of the 
gases without porous septa by Prof. Loschmidt. The author 
had investigated the rapidity of diffusion of two gases superim- 
posed in layers and in contact upon a horizontal plane. His 
experiments related to air and carbonic acid, carbonic acid and 
hydrogen, and hydrogen and oxygen. Their chief result is the 
law of the proportionality of the constants of diffusion with the 
