Marcu 4, 1915] 
NATURE 27 


view that true disseminated sclerosis is due to a 
specific morbid agent, the nature of which is quite 
unknown. Histological evidence suggests a soluble 
toxin, conveyed to the nervous tissues by the blood 
channel rather than by lymphatics. ‘The fleeting early 
motor paralysis and- psychical symptoms may be related 
to the presence of areas in association paths, their 
remission being possibly due to the linking up of 
other association paths, or their compensation to the 
opening up of new paths. Although approximate 
answers may be given to questions relating to the 
nature of the process, to its origin, and to certain 
aspects of the mode of action, we are still quite in 
the dark concerning the nature of the final causal 
agent, which determines a disease which, however 
variable the early symptoms, conceals its characteristic 
course only temporarily. 
February 15.—Dr. Peach, vice-president, in the 
chair.—Dr. H. Rainy and Dr. J. W. Ballantyne : Skia- 
graphic researches in teratology. The paper dealt with 
the abnormal development of bones in the human 
foetus, and was illustrated by a number of X-ray 
photographs of these abnormalities. The facts 
brought forward opened up important  ques- 
tions in heredity, as well as in development.— 
Prof. J. Stephenson: (1) On Haemonais laurentii, a 
representative of a little-known genus of Naidide; 
(2) on a rule of proportion observed in the Sete of 
certain Naidide; (3) on the sexual phase in certain 
of the Naidide. An account was given in these 
connected papers of the various systems of organs 
and of the process of fission in this group of worms. 
A curious feature in two of the species described was 
the degeneration of the alimentary canal as the worm 
approached sexual maturity. Dr. F. R. Cowper Reed: 
The Ordovician and Silurian Brachiopoda of the Girvan 
District. In this elaborate memoir about 250 species 
and varieties were described, of which some seventy 
were new to science. The greater number of specimens 
described were from the collection made by Mrs. 
Robert Gray of Edinburgh, and with these were joined 
specimens from various museums in Great Britain. 
The local facies of the fauna were strongly marked; 
but many of the species, particularly those of Ordo- 
vician age, resembled American rather than European 
types. A characteristic feature was the limitation of 
distinctive species to successive stratigraphical horizons, 
a fact which suggested a more extended use of 
brachiopods for zonal purposes. 
Paris. 
Academy of Sciences, February 15.—M. Ed. Perrier in 
the chair.—L. E. Bertin: The transport of marine 
mines by currents under the action of the ground- 
swell. The upward thrust on the mine due to hydro- 
static pressure has been usually calculated from the 
value in water at rest. The alterations in the thrust 
due to an oscillatory motion of the water are calculated, 
and it is shown that to prevent the anchor being lifted 
its customary weight should be doubled.—C, Guichard : 
Surfaces such that the lines of curvature correspond 
on the primitive surface, and on the surface locus of 
the centres of the spheres osculating the lines of 
curvature of a series of the primitive surface.—Paul 
Vuillemin: The flower. A discussion of the flower in 
its relation to the leaves.—B. Jekhowsky : Observations 
of Delavan’s comet, 1913f, made at the Observa- 
tory of Paris. Four positions given for January 8 and 
11. The comet appeared as a rounded nebulosity of 
about 30” diameter with a semi-stellar nucleus. Mag- 
nitude 7-5 to 8. No tail.—M. Alezais: A property of 
arithmetical progressions.—M. _— Globa-Mikhailenko : 
Ellipsoidal figures of equilibrium of a fluid mass in 
No. 2366, VOL. 95| 
! 

i The 
rotation when capillary pressuse is taken into account. 
It is shown that the only ellipsoidal figure of equili- 
brium assumed by a fluid mass in rotation, it the 
surface tension is taken into account, is the cylinder 
of revolution.—A. Guillet ; Wheel with harmonic teeth, 
application to the construction of a laboratory chrono- 
meter with a uniform and continuous movement.—E. 
Mathias, H. Kamerlingh Onnes, and C. A. Crommelin : 
The rectilinear diameter of nitrogen. The densities 
of liquid nitrogen and its saturated vapour were deter- 
mined at temperatures ranging from —208-36° C. to 
—148-08° C., and the values of the ordinate of the 
diameter were found to be y=0:022904—0-0019577 4. 
angular coefficient of the diameter 
—o-0019577, and the critical density A=o0-3 1096. 
is 
o— 
The 
ang ee ROA . 
critical coefficient ——— is 3-421, or nearly the same 
= j 
as argon (3-424) and oxygen (3-419).—L. Bouchet : 
The deformation of vulcanised indiarubber under the 
action of an electrostatic field. The variable electro- 
static pressures are sufficient to account for the ob- 
served facts without any additional hypothesis.— 
Keivin Burns: Interferential measurements of wave- 
lengths in the ultra-violet part of the iron spectrum 
Data are given for wave-lengths between 2551 and 
3701 on the basis of the value 6438.4696 for the red 
cadmium line.—Henry Hubert: Preliminary sketch oi 
the geology of the Ivory Coast.—B. Galitzine : The 
earthquake in Italy on January 13, 1915. Particulars 
of the records on the seismographs at the Pulkovo 
Observatory. The position of the epicentre calculated 
from the seismograms coincided very closely with the 
region of greatest damage, and it is pointed out that 
observations from a single station were sufficient for 
this determination.—Ph. Flajolet : Disturbances of the 
magnetic declination at Lyons (Saint-Genis-Laval) 
during the second quarter of 1914.—Henri Coupin: A 
marine yeast. The first example of a yeast isolated 
from sea water, for which the name Torula marina is 
proposed.—M. Coquidé : Remark on the nitrification in 
the peaty soils in the neighbourhood of Laon. The 
experiments were made on virgin soil and included 
the addition of potassium chloride or kainit, sodium 
nitrate, and phosphate slag, the three types being used 
separately, in pairs, or all together, the last giving 
the best results. The effect of omitting nitrate was 
marked, and there appears to be little or no natural 
nitrification of the nitrogenous material in these soils. 
—J. Bergonié : The mobilisation in the tissues of mag- 
netic projectiles by the repeated application of electro- 
magnetism. To move deeply-seated metallic fragments 
repeated applications of an electromagnet may be 
required, leading ultimately to a swelling on the. sur- 
face exactly localising the fragment, and permitting 
its easy extraction by a simple operation. Details of 
cases are given in which the original position of the 
piece of shell was too deep-seated for direct removal, 
or in which unsuccessful operations after X-ray locali- 
sation had been made.—Raoul Bayeux : The treatment 
of hydrarthosis and hemarthrosis by intra-articular 
pneumatic compression by means of oxygen.—A. 
Pezard: The experimental transformation of the 
secondary sexual characters in the Gallinacez.—aA. 
Sartory, L. Spillmann, and Ph. Lasseur : Contribution to 
the study of typhoid states. Although the causal 
origin of typhoid fever is the Eberth bacillus, it 
appears to be probable that the pathogenic power of 
this organism may be increased by the presence of 
other micro-organisms, such as Proteus vulgaris, a 
diplococcus described by the authors, and possibly 
other pathogenic species. It is also possible that life 
in the trenches may give rise to a new clinical type of 
typhoid fever. 
